Celery Cultivar ADS-20

ABSTRACT

A celery cultivar, designated ADS-20, is disclosed. The invention relates to the seeds of celery cultivar ADS-20, to the plants of celery cultivar ADS-20 and to methods for producing a celery plant by crossing the cultivar ADS-20 with itself or another celery cultivar. The invention further relates to methods for producing a celery plant containing in its genetic material one or more transgenes and to the transgenic celery plants and plant parts produced by those methods. This invention also relates to celery cultivars or breeding cultivars and plant parts derived from celery cultivar ADS-20, to methods for producing other celery cultivars, lines or plant parts derived from celery cultivar ADS-20 and to the celery plants, varieties, and their parts derived from the use of those methods. The invention further relates to hybrid celery seeds, plants, and plant parts produced by crossing cultivar ADS-20 with another celery cultivar.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinctive celery (Apiumgraveolens var. dulce) variety, designated ADS-20. All publicationscited in this application are herein incorporated by reference.

There are numerous steps in the development of any novel, desirableplant germplasm. Plant breeding begins with the analysis, definition ofproblems and weaknesses of the current germplasm, the establishment ofprogram goals, and the definition of specific breeding objectives. Thenext step is selection of germplasm that possesses the traits to meetthe program goals. The goal is to combine in a single variety or hybridan improved combination of desirable traits from the parental germplasm.These important traits may include improved flavor, increased stalk sizeand weight, higher seed yield, improved color, resistance to diseasesand insects, tolerance to drought and heat, and better agronomicquality.

All cultivated forms of celery belong to the species Apium graveolensvar. dulce that is grown for its edible stalk. As a crop, celery isgrown commercially wherever environmental conditions permit theproduction of an economically viable yield. In the United States, theprincipal growing regions are California, Florida, Texas, Arizona andMichigan. Fresh celery is available in the United States year-round,although the greatest supply is from November through January. Forplanting purposes, the celery season is typically divided into twoseasons: summer and winter, with Florida, Texas and the southernCalifornia areas harvesting from November to July, and Michigan andnorthern California harvesting from July to October. Celery is consumedas fresh, raw product and as a cooked vegetable.

Celery is a cool-season biennial that grows best from 60° F. to 65° F.(16° C. to 18° C.), but will tolerate temperatures from 45° F. to 75° F.(7° C. to 24° C.). Freezing damages mature celery by splitting thepetioles or causing the skin to peel, making the stalks unmarketable.This can be a problem for crops planted in the winter regions; however,celery can tolerate minor freezes early in the season.

The two main growing regions for celery in California are located alongthe Pacific Ocean: the central coast or summer production area(Monterey, San Benito, Santa Cruz and San Luis Obispo Counties) and thesouth coast or winter production area (Ventura and Santa BarbaraCounties). A minor region (winter) is located in the southern deserts(Riverside and Imperial Counties).

In the south coast, celery is transplanted from early August to Aprilfor harvest from November to mid-July; in the Santa Maria area, celeryis transplanted from January to August for harvest from April throughDecember. In the central coast, fields are transplanted from March toSeptember for harvest from late June to late December. In the southerndeserts, fields are transplanted in late August for harvest in January.

Commonly used celery varieties for coastal production include Tall Utah52-75, Conquistador and Sonora. Some shippers use their own proprietaryvarieties. Celery seed is very small and difficult to germinate. Allcommercial celery is planted as greenhouse-grown transplants. Celerygrown from transplants is more uniform than from seed and takes lesstime to grow the crop in the field. Transplanted celery is traditionallyplaced in double rows on 40-inch (100-cm) beds with plants spacedbetween 6.0 and 7 inches apart.

Celery requires a relatively long and cool growing season (Thephysiology of vegetable crops by Pressman, CAB Intl., New York, 1997).Earlier transplanting results in a longer growing season, increasedyields, and better prices. However, celery scheduled for Spring harvestoften involves production in the coolest weather conditions of Winter, aperiod during which vernalization can occur. If adequate vernalizationoccurs for the variety, bolting may be initiated. Bolting is thepremature rapid elongation of the main celery stem into a floral axis(i.e., during the first year for this normally biennial species).Bolting slows growth as the plant approaches marketable size leaves astalk with no commercial value. Different varieties have differentvernalization requirements, but in the presence of bolting, the lengthof the seed stem can be used as a means of measuring bolting tolerancethat exists in each different variety. The most susceptible varietiesreach their vernalization requirement earlier and have time to developthe longest seed stems, while the moderately tolerant varieties takelonger to reach their vernalization requirement and have less time todevelop a seed stem which would therefore be shorter. Under normalproduction conditions, the most tolerant varieties may not achieve theirvernalization requirement and therefore not produce a measurable seedstem.

The coldest months when celery is grown in the United States areDecember, January and February. If celery is going to reach itsvernalization requirements to cause bolting, it is generally youngercelery that is exposed to this cold weather window. This celerygenerally matures in the months of April and May which constitutes whatthe celery industry calls the bolting or seeder window. The bolting orseeder window is a period where seed stems are generally going to impactthe quality of the marketable celery and this is most consistentlyexperienced in celery grown in the Southern California region. Thepresence of seed stems in celery can be considered a major marketabledefect as set forth in the USDA grade standards. If the seed stem islonger than twice the diameter of the celery stalk or eight inches, thecelery no longer meets the standards of US Grade #1. If the seed stem islonger than three times the diameter of the celery stalk, the celery isno longer marketable as US Grade #2 (United States Standards for Gradesof Celery, United States Department of Agriculture, reprinted January1997).

Celery is an allogamous biennial crop. The celery genome consists of 11chromosomes. Its high degree of out-crossing is accomplished by insectsand wind pollination. Pollinators of celery flowers include a largenumber of wasp, bee and fly species. Celery is subject to inbreedingdepression, which appears to be dependent upon the genetic background assome lines are able to withstand selfing for three or four generations.

Celery flowers are protandrous, with pollen being released 3-6 daysbefore stigma receptivity. At the time of stigma receptivity the stamenswill have fallen and the two stigmata unfolded in an upright position.The degree of protandry varies, which makes it difficult to performreliable hybridization, due to the possibility of accidental selfing.

Celery flowers are very small, which significantly hinders easy removalof individual anthers. Furthermore, different developmental stages ofthe flowers in umbels makes it difficult to avoid uncontrolledpollinations. The standard hybridization technique in celery consists ofselecting flower buds of the same size and eliminating the older andyounger flowers. Then, the umbellets are covered with glycine paper bagsfor a 5-10 day period, during which the stigmas become receptive. At thetime the flowers are receptive, available pollen or umbellets sheddingpollen from selected male parents are rubbed on to the stigmas of thefemale parent.

Celery plants require a period of vernalization while in the vegetativephase in order to induce seed stalk development. A period of 6-10 weeksat 5° C. to 8° C. when the plants are greater than 4 weeks old isusually adequate. Due to a wide range of responses to the coldtreatment, it is often difficult to synchronize crossing, since plantswill flower at different times. However, pollen can be stored for 6-8months at −10° C. in the presence of silica gel or calcium chloride witha viability decline of only 20-40%, thus providing flexibility toperform crosses over a longer time.

For selfing, the plant or selected umbels are caged in cloth bags. Theseare shaken several times during the day to promote pollen release.Houseflies (Musca domestica) can also be introduced weekly into the bagsto perform pollinations.

Choice of breeding or selection methods depends on the mode of plantreproduction, the heritability of the trait(s) being improved, and thetype of cultivar used commercially (e.g., F₁ hybrid cultivar, purelinecultivar, etc.). For highly heritable traits, a choice of superiorindividual plants evaluated at a single location will be effective,whereas for traits with low heritability, selection should be based onmean values obtained from replicated evaluations of families of relatedplants. Popular selection methods commonly include pedigree selection,modified pedigree selection, mass selection, and recurrent selection.

The complexity of inheritance influences the choice of breeding method.Backcross breeding is used to transfer one or a few favorable genes fora highly heritable trait into a desirable cultivar. This approach hasbeen used extensively for breeding disease-resistant cultivars. Variousrecurrent selection techniques are used to improve quantitativelyinherited traits controlled by numerous genes. The use of recurrentselection in self-pollinating crops depends on the ease of pollination,the frequency of successful hybrids from each pollination, and thenumber of hybrid offspring from each successful cross.

Each breeding program should include a periodic, objective evaluation ofthe efficiency of the breeding procedure. Evaluation criteria varydepending on the goal and objectives, but should include gain fromselection per year based on comparisons to an appropriate standard, theoverall value of the advanced breeding lines, and the number ofsuccessful cultivars produced per unit of input (e.g., per year, perdollar expended, etc.).

Promising advanced breeding lines are thoroughly tested and compared toappropriate standards in environments representative of the commercialtarget area(s) for at least three years. The best lines are candidatesfor new commercial cultivars; those still deficient in a few traits areused as parents to produce new generations for further selection.

These processes, which lead to the final step of marketing anddistribution, usually take from ten to twenty years from the time thefirst cross or selection is made. Therefore, development of newcultivars is a time-consuming process that requires precise forwardplanning, efficient use of resources, and a minimum of changes indirection.

A most difficult task is the identification of individuals that aregenetically superior, because for most traits the true genotypic valueis masked by other confounding plant traits or environmental factors.One method of identifying a superior plant is to observe its performancerelative to other experimental plants and to a widely grown standardcultivar. If a single observation is inconclusive, replicatedobservations provide a better estimate of its genetic worth.

The goal of celery plant breeding is to develop new, unique and superiorcelery cultivars. The breeder initially selects and crosses two or moreparental lines, followed by repeated selfing and selection, producingmany new genetic combinations. The breeder can theoretically generatebillions of different genetic combinations via crossing, selfing andmutations. The breeder has no direct control at the cellular level.Therefore, two breeders will never develop the same line, or even verysimilar lines, having the same celery traits.

Each year, the plant breeder selects the germplasm to advance to thenext generation. This germplasm is grown under unique and differentgeographical, climatic and soil conditions and further selections arethen made, during and at the end of the growing season. The cultivarsthat are developed are unpredictable. This unpredictability is becausethe breeder's selection occurs in unique environments, with no controlat the DNA level (using conventional breeding procedures), and withmillions of different possible genetic combinations being generated. Abreeder of ordinary skill in the art cannot predict the final resultinglines he/she develops, except possibly in a very gross and generalfashion. The same breeder cannot produce the same line twice by usingthe exact same original parents and the same selection techniques. Thisunpredictability results in the expenditure of large research monies todevelop superior celery cultivars.

The development of commercial celery cultivars often starts with crossesbetween different commercial varieties and/or germplasm at differentstages in development. Pedigree breeding and recurrent selectionbreeding methods are used to develop cultivars from breedingpopulations. Breeding programs combine desirable traits from two or morevarieties or various broad-based sources into breeding pools from whichcultivars are developed by selfing and selection of desired phenotypes.The new cultivars are crossed with other varieties and the hybrids fromthese crosses are evaluated to determine which have commercialpotential.

Pedigree breeding is used commonly for the improvement ofself-pollinating crops or inbred lines of cross-pollinating crops. Twoparents which possess favorable, complementary traits are crossed toproduce an F₁. An F₂ population is produced by selfing one or severalF₁'s or by intercrossing two F₁'s (sib mating). Selection of the bestindividuals usually begins in the F₂ population; then, beginning in theF₃, the best individuals in the best families are selected. Replicatedtesting of families, or hybrid combinations involving individuals ofthese families, often follows in the F₄ generation to improve theeffectiveness of selection for traits with low heritability. At anadvanced stage of inbreeding (i.e., F₆ and F₇), the best lines ormixtures of phenotypically similar lines are tested for potentialrelease as new cultivars.

Mass and recurrent selections can be used to improve populations ofeither self- or cross-pollinating crops. A genetically variablepopulation of heterozygous individuals is either identified or createdby intercrossing several different parents. The best plants are selectedbased on individual superiority, outstanding progeny, or excellentcombining ability. The selected plants are intercrossed to produce a newpopulation in which further cycles of selection are continued.

Backcross breeding has been used to transfer genes for a simplyinherited, highly heritable trait into a desirable homozygous cultivaror line that is the recurrent parent. The source of the trait to betransferred is called the donor parent. The resulting plant is expectedto have the attributes of the recurrent parent (e.g., cultivar) and thedesirable trait transferred from the donor parent. After the initialcross, individuals possessing the phenotype of the donor parent areselected and repeatedly crossed (backcrossed) to the recurrent parent.The resulting plant is expected to have the attributes of the recurrentparent (e.g., cultivar) and the desirable trait transferred from thedonor parent.

In the strictest sense, the single-seed descent procedure refers toplanting a segregating population, harvesting a sample of one seed perplant, and using the one-seed sample to plant the next generation. Whenthe population has been advanced from the F₂ to the desired level ofinbreeding, the plants from which lines are derived will each trace todifferent F₂ individuals. The number of plants in a population declineseach generation due to failure of some seeds to germinate or some plantsto produce at least one seed. As a result, not all of the F₂ plantsoriginally sampled in the population will be represented by a progenywhen generation advance is completed.

In addition to phenotypic observations, the genotype of a plant can alsobe examined. There are many laboratory-based techniques available forthe analysis, comparison and characterization of a plants genotype.Among these are Isozyme Electrophoresis, Restriction Fragment LengthPolymorphisms (RFLPs), Randomly Amplified Polymorphic DNAs (RAPDs),Arbitrarily Primed Polymerase Chain Reaction (AP-PCR), DNA AmplificationFingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs),Amplified Fragment Length polymorphisms (AFLPs), Simple Sequence Repeats(SSRs—which are also referred to as Microsatellites), and SingleNucleotide Polymorphisms (SNPs).

Isozyme Electrophoresis and RFLPs have been widely used to determinegenetic composition. Shoemaker and Olsen, (Molecular Linkage Map ofSoybean (Glycine max) p. 6.131-6.138 in S. J. O'Brien (ed) Genetic Maps:Locus Maps of Complex Genomes, Cold Spring Harbor Laboratory Press, ColdSpring Harbor, N.Y., (1993)) developed a molecular genetic linkage mapthat consisted of 25 linkage groups with about 365 RFLP, 11 RAPD, threeclassical markers and four isozyme loci. See also, Shoemaker, R. C.,RFLP Map of Soybean, p 299-309, in Phillips, R. L. and Vasil, I. K.,eds. DNA-Based Markers in Plants, Kluwer Academic Press, Dordrecht, theNetherlands (1994).

SSR technology is currently the most efficient and practical markertechnology; more marker loci can be routinely used and more alleles permarker locus can be found using SSRs in comparison to RFLPs. Forexample, Diwan and Cregan described a highly polymorphic microsatellitelocus in soybean with as many as 26 alleles. (Diwan, N. and Cregan, P.B., Theor. Appl. Genet. 95:22-225, 1997.) SNPs may also be used toidentify the unique genetic composition of the invention and progenyvarieties retaining that unique genetic composition. Various molecularmarker techniques may be used in combination to enhance overallresolution.

Molecular markers, which include markers identified through the use oftechniques such as Isozyme Electrophoresis, RFLPs, RAPDs, AP-PCR, DAF,SCARs, AFLPs, SSRs, and SNPs, may be used in plant breeding. One use ofmolecular markers is Quantitative Trait Loci (QTL) mapping. QTL mappingis the use of markers which are known to be closely linked to allelesthat have measurable effects on a quantitative trait. Selection in thebreeding process is based upon the accumulation of markers linked to thepositive effecting alleles and/or the elimination of the markers linkedto the negative effecting alleles from the plant's genome.

Molecular markers can also be used during the breeding process for theselection of qualitative traits. For example, markers closely linked toalleles or markers containing sequences within the actual alleles ofinterest can be used to select plants that contain the alleles ofinterest during a backcrossing breeding program. The markers can also beused to select toward the genome of the recurrent parent and against themarkers of the donor parent. This procedure attempts to minimize thegenomic contribution from the donor parent that remains in the selectedplants, and can reduce the number of back-crosses necessary to generatecoisogenic plants. This procedure is often called genetic markerenhanced selection or marker-assisted selection. Molecular markers mayalso be used to identify and exclude certain sources of germplasm asparental varieties or ancestors of a plant by providing a means oftracking genetic profiles through crosses.

Mutation breeding is another method of introducing new traits intocelery varieties. Mutations that occur spontaneously or are artificiallyinduced can be useful sources of variability for a plant breeder. Thegoal of artificial mutagenesis is to increase the rate of mutation for adesired characteristic. Mutation rates can be increased by manydifferent means including temperature, long-term seed storage, tissueculture conditions, radiation (such as X-rays, Gamma rays, neutrons,Beta radiation, or ultraviolet radiation), chemical mutagens (such asbase analogs like 5-bromo-uracil), alkylating agents (such as sulfurmustards, nitrogen mustards, epoxides, ethyleneamines, sulfates,sulfonates, sulfones, or lactones), azide, hydroxylamine, nitrous acidor acridines. Once a desired phenotype is observed the genetic mutationresponsible for that trait may then be incorporated into existinggermplasm by traditional breeding techniques. Details of mutationbreeding can be found in Principles of Cultivar Development by Fehr,Macmillan Publishing Company, 1993.

The production of double haploids can also be used for the developmentof homozygous varieties in a breeding program. Double haploids areproduced by doubling a set of chromosomes from a heterozygous plant toproduce a completely homozygous individual. For example, see Wan et al.,Theor. Appl. Genet., 77:889-892, 1989.

Descriptions of other breeding methods that are commonly used fordifferent traits and crops can be found in several reference books(e.g., Principles of Plant Breeding John Wiley and Son, pp. 115-161,1960; Allard, 1960; Simmonds, 1979; Sneep et al., 1979; Fehr, 1987; ACarrots and Related Vegetable Umbelliferae@, Rubatzky, V. E., et al.,1999).

Proper testing should detect any major faults and establish the level ofsuperiority or improvement over current cultivars. In addition toshowing superior performance, there must be a demand for a new cultivarthat is compatible with industry standards or which creates a newmarket. The introduction of a new cultivar will incur additional coststo the seed producer, the grower, processor and consumer for specialadvertising and marketing, altered seed and commercial productionpractices, and new product utilization. The testing preceding release ofa new cultivar should take into consideration research and developmentcosts as well as technical superiority of the final cultivar. Forseed-propagated cultivars, it must be feasible to produce seed easilyand economically.

Celery in general is an important and valuable vegetable crop. Thus, acontinuing goal of celery plant breeders is to develop stable, highyielding celery cultivars that are agronomically sound to maximize theamount of yield produced on the land. To accomplish this goal, thecelery breeder must select and develop celery plants that have thetraits that result in superior cultivars.

The foregoing examples of the related art and limitations relatedtherewith are intended to be illustrative and not exclusive. Otherlimitations of the related art will become apparent to those of skill inthe art upon a reading of the specification.

SUMMARY OF THE INVENTION

The following embodiments and aspects thereof are described inconjunction with systems, tools, and methods which are meant to beexemplary and illustrative, not limiting in scope. In variousembodiments, one or more of the above-described problems have beenreduced or eliminated, while other embodiments are directed to otherimprovements.

According to the invention, there is provided a novel celery cultivardesignated ADS-20. This invention thus relates to the seeds of celerycultivar ADS-20, to the plants of celery cultivar ADS-20 and to methodsfor producing a celery plant by crossing celery ADS-20 with itself oranother celery plant, to methods for producing a celery plant containingin its genetic material one or more transgenes and to the transgeniccelery plants produced by that method. This invention also relates tomethods for producing other celery cultivars derived from celerycultivar ADS-20 and to the celery cultivar derived by the use of thosemethods. This invention further relates to hybrid celery seeds andplants produced by crossing celery cultivar ADS-20 with another celeryline.

In another aspect, the present invention provides regenerable cells foruse in tissue culture of celery cultivar ADS-20. The tissue culture willpreferably be capable of regenerating plants having essentially all ofthe physiological and morphological characteristics of the foregoingcelery plant, and of regenerating plants having substantially the samegenotype as the foregoing celery plant. Preferably, the regenerablecells in such tissue cultures will be callus, protoplasts, meristematiccells, leaves, pollen, embryos, roots, root tips, anthers, pistils,flowers, seeds, petioles and suckers. Still further, the presentinvention provides celery plants regenerated from the tissue cultures ofthe invention.

Another aspect of the invention is to provide methods for producingother celery plants derived from celery cultivar ADS-20. Celerycultivars derived by the use of those methods are also part of theinvention.

The invention also relates to methods for producing a celery plantcontaining in its genetic material one or more transgenes and to thetransgenic celery plant produced by those methods.

In another aspect, the present invention provides for single geneconverted plants of ADS-20. The single transferred gene may preferablybe a dominant or recessive allele. Preferably, the single transferredgene will confer such traits as male sterility, herbicide resistance,insect resistance, modified fatty acid metabolism, modified carbohydratemetabolism, resistance for bacterial, fungal, or viral disease, malefertility, enhanced nutritional quality and industrial usage or thetransferred gene will have no apparent value except for the purpose ofbeing a marker for variety identification. The single gene may be anaturally occurring celery gene or a transgene introduced throughgenetic engineering techniques.

The invention further provides methods for developing celery plant in acelery plant breeding program using plant breeding techniques includingrecurrent selection, backcrossing, pedigree breeding, restrictionfragment length polymorphism enhanced selection, genetic marker enhancedselection and transformation. Seeds, celery plants, and parts thereof,produced by such breeding methods are also part of the invention.

In addition to the exemplary aspects and embodiments described above,further aspects and embodiments will become apparent by reference by thestudy of the following descriptions.

DEFINITIONS

In the description and tables which follow, a number of terms are used.In order to provide a clear and consistent understanding of thespecification and claims, including the scope to be given such terms,the following definitions are provided:

Allele. An allele is any of one or more alternative form of a gene, allof which relate to one trait or characteristic. In a diploid cell ororganism, the two alleles of a given gene occupy corresponding loci on apair of homologous chromosomes.

Backcrossing. Backcrossing is a process in which a breeder repeatedlycrosses hybrid progeny back to one of the parents, for example, a firstgeneration hybrid F₁ with one of the parental genotype of the F₁ hybrid.

Blackheart. Blackheart is due to a lack of movement of sufficientcalcium that causes the plant to turn brown and begin to decay at thegrowing point of the plant. Celery in certain conditions, such as warmweather, grows very rapidly and is incapable of moving sufficientamounts of calcium to the growing point.

Bolting. The premature development of a flowering or seed stalk, andsubsequent seed, before a plant produces a food crop. Bolting istypically caused by late planting when temperatures are low enough tocause vernalization of the plants.

Bolting Period. Also known as the bolting or seeder window, andgenerally occurs in celery that is transplanted from the middle ofDecember through January and matures in April to May. The intensity andactual weeks that bolting may be observed vary from year to year, but itis generally observed in this window.

Bolting Tolerance. The amount of vernalization that is required fordifferent celery varieties to bolt is genetically controlled. Varietieswith increased tolerance to bolting require greater periods ofvernalization in order to initiate bolting. A comparison of boltingtolerance between varieties can be measured by the length of theflowering or seed stem under similar vernalization conditions.

Brown Stem. A disease caused by the bacterium Pseudomonas cichorii thatcauses petiole necrosis. Brown Stem is characterized by a firm, browndiscoloration throughout the petiole.

Celeriac or Root celery (Apium graveolens L. var. rapaceum). A plantthat is related to celery but instead of having a thickened andsucculent leaf petiole as in celery, celeriac has an enlarged hypocotyland upper root that is the edible product.

Celery Heart. The center most interior petioles and leaves of the celerystalk. They are not only the smallest petioles in the stalk, but theyoungest as well. Some varieties are considered heartless because theygo right from very large petioles to only a couple of very smallpetioles. The heart is comprised of the petioles that are closest to themeristem of the celery stalk. Most straw and process type varieties havevery little heart development.

Consumable. Means material that is edible by humans.

Crackstem. The petiole can crack or split horizontally orlongitudinally. Numerous cracks in several locations along the petioleare often an indication that the variety has insufficient boronnutrition. A variety's ability to utilize boron is a physiologicalcharacteristic which is genetically controlled.

Dry weight. The weight of the celery after all water has been removedfrom celery.

Dry weight percentage. The calculation of the dry weight of the celerydivided by the original weight of the celery before the removal of thewater.

Durable. Means long-lasting, sturdy and resilient celery, that is ableto resist breakage and ruptures through normal harvesting, processing,packaging, shipment and usage.

Edible celery (Apium graveolens L. var. dulce). An Apium graveolens L.var. dulce celery that is considered suitable for ingestion by humansbased upon the flavor and the texture of the celery.

Efficiency. Efficiency as presented here is the percentage by weight ofthe four-inch or three-inch sticks compared to the gross weight. Moreefficient varieties have a greater percentage of the gross weight beingconverted into useable finished product (i.e., four-inch or three-inchsticks).

Essentially all the physiological and morphological characteristics. Aplant having essentially all the physiological and morphologicalcharacteristics of the recurrent parent, except for the characteristicsderived from the converted gene.

External diameter. The average diameter of the petiole cylinder measuredfrom the outside of the cylinder wall to the outside of the oppositecylinder wall.

Feather Leaf. Feather Leaf is a yellowing of the lower leaves andgenerally occurs in the outer petioles but can also be found on innerpetioles of the stalk. These yellowing leaves which would normallyremain in the harvested stalk are considered unacceptable. Thesepetioles then have to be stripped off in order to meet USDA standardswhich effectively decreases the stalk size and yield.

Flare. The lower, generally wider portion of the petiole which isusually a paler green or white.

Fusarium Yellows. A fungal soilborne disease caused by Fusariumoxysporum f. sp. apii Race 2. Infected plants turn yellow and arestunted. Some of the large roots may have a dark brown and awater-soaked appearance. The water-conducting tissue (xylem) in thestem, crown, and root show a characteristic orange-brown discoloration.In the later stages of infection, plants remain severely stunted andyellowed and may collapse.

Gene. As used herein, “gene” refers to a segment of nucleic acid. A genecan be introduced into a genome of a species, whether from a differentspecies or from the same species, using transformation or variousbreeding techniques.

Gross Yield (Pounds/Acre). The total yield in pounds/acre of trimmedcelery plants (stalks).

Internal diameter. The average diameter of the petiole cylinder measuredfrom the inside of the cylinder wall to the inside of the oppositecylinder wall.

Leaf Celery (Apium graveolens L. var. secalinum). A plant that has beendeveloped primarily for leaf and seed production. Often grown inMediterranean climates, leaf celery more closely resembles celery's wildancestors. The stems are small and fragile and vary from solid to hollowand the leaves are fairly small and are generally bitter. This type isoften used for its medicinal properties and spice.

Leaf Margin Chlorosis. A magnesium deficiency producing an interveinalchlorosis which starts at the margin of leaves.

Maturity Date. Maturity in celery can be dictated by two conditions. Thefirst, or true maturity, is the point in time when the celery reachesmaximum size distribution, but before defects such as pith, yellowing,Feather Leaf or Brown Stem appear. The second, or market maturity is anartificial maturity dictated by market conditions, i.e, the marketrequirement may be for 3 dozen sizes so the field is harvested atslightly below maximum yield potential because the smaller sizes arewhat the customers prefer at that moment.

MUN. MUN refers to the MUNSELL Color Chart which publishes an officialcolor chart for plant tissues according to a defined numbering system.The chart may be purchased from the Macbeth Division of KollmorgenInstruments Corporation, 617 Little Britain Road, New Windsor, New York12553-6148.

Petiole. A petiole is the stem or limb of a leaf, the primary portion ofthe celery consumed.

Pith. Pith is a sponginess/hollowness/white discoloration that occurs inthe petioles of varieties naturally as they become over-mature. In somevarieties it occurs at an earlier stage causing harvest to occur priorto ideal maturity. Pith generally occurs in the outer older petiolesfirst. If it occurs, these petioles are stripped off to make grade andeffectively decreases the stalk size and overall yield potential.

Petiole depth. The average measurement in millimeters of the depth ofthe celery petiole at its narrowest point. The petiole depth measurementis taken from the outside of the petiole (which is the part of thepetiole that faces the outside of the stalk) and is measured to theinside of the petiole or cup or the inner most point of the petiole thatfaces the center of the stalk or heart.

Petiole width. The average measurement of the width of the celerypetiole in millimeters at its widest point. The measurement is takenfrom the side or edge of petiole to the opposite side or edge of thepetiole. The measurement is taken 90 degrees from petiole depth.

Phthalides. One of the chemical compounds that are responsible for thecharacteristic flavor and aroma of celery.

Plant Height. The height of the plant from the bottom of the base orbutt of the celery plant to the top of the tallest leaf.

Quantitative Trait Loci. Quantitative Trait Loci (QTL) refers to geneticloci that control to some degree, numerically representable traits thatare usually continuously distributed.

Regeneration. Regeneration refers to the development of a plant fromtissue culture.

Ribbing. The texture of the exterior surface of the celery petiole canvary from smooth to ribby depending on the variety. Ribbing is thepresence of numerous ridges that run vertically along the petioles ofthe celery plant.

Sanitized. Means washed, cleansed or sterilized celery so the limb'ssurface is free of dirt, insects, microbial infestation, bacterialinfestation, fungal infestation or other surface contaminates. Theprocess of sanitization involves washing the limbs in order to removesurface contamination such as dirt and insects and the utilization of asanitization material or process in order to remove or kill surfacecontamination by microbial, bacterial and fungal agents.

Sanitization Treatment. Treating celery with a chemical or process so asto sanitize the celery. The chemical or process is selected from thegroup consisting of ascorbic acid, peroxyacetic acid also known asTSUNAMI, sodium hypochlorite (chlorine), bromine products (sodiumhypobromine), chlorine dioxide, ozone based systems, hydrogen peroxideproducts, trisodium phosphate, quaternary ammonium products, ultravioletlight systems, irradiation, steam, ultra heat treatments, and highpressure pasteurization.

Shear strength or pressure. Means the force in grams that a celery canwithstand prior rupturing or cutting of the wall of the celery petiole.

Seed Stem. A seed stem is the result of the elongation of the main stemof the celery, which is usually very compressed to almost non-existent,to form the flowering axis. The seed stem or flowering axis can reachseveral feet in height during full flower. The length of the seed stemis measured as the distance from the top of the basal plate (the base ofthe seed stem) to its terminus (the terminal growing point).

Single gene converted. Single gene converted or conversion plant refersto plants which are developed by backcrossing, or via geneticengineering, wherein essentially all of the desired morphological andphysiological characteristics of a line are recovered in addition to thesingle gene transferred into the line via the backcrossing technique orvia genetic engineering.

Stalk. A stalk is a single celery plant that is trimmed with the top orfoliage and the roots removed.

Stringiness. Stringiness is a physiological characteristic that isgenerally associated with strings that get stuck between the consumer'steeth. There are generally two sources of strings in celery. One is thevascular bundle which can be fairly elastic and behave as a string. Thesecond is a strip of particularly strong epidermis cells calledschlerenchyma which are located on the surface of the ridges of thecelery varieties that have ribs.

Suckers. Suckers are auxiliary shoots that form at the base of the stalkor within the auxiliary buds between each petiole. If these shoots formbetween the petioles of the stalk, several petioles have to be strippedoff causing the celery to become smaller and the functional yields to bedecreased.

Theoretical Maximum Yield. If you assume 100% 2 dozen size and a 47,000plant population per acre and 70 pound cartons, your theoretical maximumyield would be 68.5 tons.

Vascular Bundle. In celery, the xylem and phloem run vertically throughthe petiole near the epidermis in groups or traces called vascularbundles.

Vacuum. The negative pressure (in inches mercury) required to rupture orbreak the celery petiole, measured in inches of mercury.

Vegetable material. Means products that are derived from, but notlimited to, vegetables, fruit, grains and other plants.

DETAILED DESCRIPTION OF THE INVENTION

Celery cultivar ADS-20 is a conventional or carton celery type with theprimary purposes of being supplied to customers as a 14 inch whole stalkor in an approximately 9 inch heart configuration. It produces a verynice green, compact, cylindrical stalk that is surprisingly andespecially valuable due to its very strong bolting tolerance. Unlike,most commercial varieties (slight vernalization requirement) that boltfairly easily under conditions with moderate bolting pressure andcompared to Hill's Special that is bolting tolerant (moderatevernalization requirement), ADS-20 is very bolting tolerant (highvernalization requirement). This increased tolerance to bolting(requirement for an increased vernalization period) means cultivarADS-20 can be grown in increasingly colder production areas with outdetrimental impact from the USDA Grade Standards. This is especiallyimportant because competition for the climatically moderated coastallands is increasing, whether by other crops or real estate. Theincreased bolting tolerance of ADS-20 also allows for celery pricing toremain fairly consistent when most production input costs areincreasing. This is possible because one of the largest costs associatedwith celery production is the component associated with land rent orprorated land value and the colder inland lands are less expensive thanpremium coastal land. ADS-20 may also be used to extend the productionwindows in the celery production areas of Northern California like SantaMaria and Salinas when the weather is to cool for the production oftraditional varieties.

Celery cultivar ADS-20 is not identified as having particularly strongtolerance to Fusarium oxysporum f. sp. apii Race 2, however, it hasslightly improved tolerance when compared with Hill's Special. Fusariumtolerance is not a critical feature for this variety because in the coolweather period when this cultivar is grown in order to capitalize on itstolerance to bolting the same temperatures that are responsible forvernalization are responsible for keeping the disease, fusarium,inactive in the soil. It is generally considered that under 50° ffusarium is not influential. Generally the only time when this maybecome an issue is late in the traditional bolting window whentemperatures can fluctuate and become elevated. If they occur, thesewarmer temperatures generally occur in May and by this time ADS-20 willhave done most of its growth and established most of its root system sofusarium has less impact on the final crop. As long as ADS-20 isconstrained to this March to May celery harvest window in the SouthernCalifornia region, it has adequate tolerance to fusarium if planted inground that has elevated fusarium levels.

Celery cultivar ADS-20 has the following morphologic and othercharacteristics (based primarily on data collected at Oxnard, Calif.).

TABLE 1 VARIETY DESCRIPTION INFORMATION Maturity: 132 days in Oxnard,California Plant Height: 72.0 cm Number of Outer Petioles (>40 cm): 12.1Number of Inner Petioles (<40 cm): 7.2 Stalk Shape: Cylindrical StalkConformation: Compact Heart Formation: Moderate to Full Petiole Length(from butt to first joint): 34.9 cm Petiole Length Class: Long (>30 cm)Petiole Width (at midpoint): 26.9 mm Petiole Thickness (at midpoint):9.9 mm Cross Section Shape: Cup Color (un-blanched at harvest): MUN 5GY6/6 (green) Anthocyanin: Absent Stringiness: Moderate Ribbing: SmoothGlossiness: Moderate Glossy Leaf Blade Color: MUN 5GY 4/4 (dark green)Bolting: Tolerant/Resistant Adaxial Crackstem (Boron Deficiency):Tolerant Abaxial Crackstem (Boron Deficiency): Tolerant Leaf MarginChlorosis (Magnesium Deficiency): Tolerant Blackheart (CalciumDeficiency): Tolerant Pithiness (Nutritional Deficiency): TolerantFeather Leaf: Tolerant Sucker Development: Tolerant Fusarium Yellows,Race 2 (Fusarium oxysporum): Slight to Moderate Tolerance Brown Stem:Tolerant

This invention is also directed to methods for producing a celery plantby crossing a first parent celery plant with a second parent celeryplant, wherein the first parent celery plant or second parent celeryplant is celery cultivar ADS-20. Further, both the first parent celeryplant and second parent celery plant may be from cultivar ADS-20.Therefore, any breeding methods using celery cultivar ADS-20 are part ofthis invention, such as selling, backcrosses, hybrid breeding, andcrosses to populations. Any plants produced using celery cultivar ADS-20as at least one parent are within the scope of this invention.

Additional methods include, but are not limited to, expression vectorsintroduced into plant tissues using a direct gene transfer method suchas microprojectile-mediated delivery, DNA injection, electroporation andthe like. More preferably, expression vectors are introduced into planttissues by using either microprojectile-mediated delivery with abiolistic device or by using Agrobacterium-mediated transformation.Transformant plants obtained with the protoplasm of the invention areintended to be within the scope of this invention.

FURTHER EMBODIMENTS OF THE INVENTION

With the advent of molecular biological techniques that have allowed theisolation and characterization of genes that encode specific proteinproducts, scientists in the field of plant biology developed a stronginterest in engineering the genome of plants to contain and expressforeign genes, or additional, or modified versions of native, orendogenous, genes (perhaps driven by different promoters) in order toalter the traits of a plant in a specific manner. Such foreignadditional and/or modified genes are referred to herein collectively as“transgenes”. Over the last fifteen to twenty years several methods forproducing transgenic plants have been developed, and the presentinvention, in particular embodiments, also relates to transformedversions of the claimed line.

Plant transformation involves the construction of an expression vectorthat will function in plant cells. Such a vector consists of DNAcomprising a gene under control of or operatively linked to a regulatoryelement (for example, a promoter). The expression vector may contain oneor more such operably linked gene/regulatory element combinations. Thevector(s) may be in the form of a plasmid, and can be used alone or incombination with other plasmids, to provide transformed celery plants,using transformation methods as described below to incorporatetransgenes into the genetic material of the celery plant(s).

Expression Vectors for Celery Transformation: Marker Genes

Expression vectors include at least one genetic marker, operably linkedto a regulatory element (a promoter, for example) that allowstransformed cells containing the marker to be either recovered bynegative selection, i.e., inhibiting growth of cells that do not containthe selectable marker gene, or by positive selection, i.e., screeningfor the product encoded by the genetic marker. Many commonly usedselectable marker genes for plant transformation are well known in thearts, and include, for example, genes that encode for enzymes thatmetabolically detoxify a selective chemical agent which may be anantibiotic or a herbicide, or genes that encode an altered target whichis insensitive to the inhibitor.

One commonly used selectable marker gene for plant transformation is theneomycin phosphotransferase II (nptII) gene, isolated from transposonTn5, which when placed under the control of plant regulatory signalsconfers resistance to kanamycin (Fraley et al., Proc. Natl. Acad. Sci.U.S.A., 80:4803 (1983)). Another commonly used selectable marker gene isthe hygromycin phosphotransferase gene which confers resistance to theantibiotic hygromycin (Vanden Elzen et al., Plant Mol. Biol., 5:299(1985)).

Additional selectable marker genes of bacterial origin that conferresistance to antibiotics include gentamycin acetyl transferase,streptomycin phosphotransferase, and aminoglycoside-3′-adenyltransferase, the bleomycin resistance determinant (Hayford et al., PlantPhysiol. 86:1216 (1988), Jones et al., Mol. Gen. Genet., 210:86 (1987),Svab et al., Plant Mol. Biol. 14:197 (1990), Hille et al., Plant Mol.Biol. 7:171 (1986)). Other selectable marker genes confer resistance toherbicides such as glyphosate, glufosinate, or bromoxynil (Comai et al.,Nature 317:741-744 (1985), Gordon-Kamm et al., Plant Cell 2:603-618(1990) and Stalker et al., Science 242:419-423 (1988)).

Selectable marker genes for plant transformation that are not ofbacterial origin include, for example, mouse dihydrofolate reductase,plant 5-enolpyruvylshikimate-3-phosphate synthase and plant acetolactatesynthase (Eichholtz et al., Somatic Cell Mol. Genet. 13:67 (1987), Shahet al., Science 233:478 (1986), Charest et al., Plant Cell Rep. 8:643(1990)).

Another class of marker genes for plant transformation require screeningof presumptively transformed plant cells rather than direct geneticselection of transformed cells for resistance to a toxic substance suchas an antibiotic. These genes are particularly useful to quantify orvisualize the spatiotemporal expression of a gene and are frequentlyreferred to as reporter genes because they are fused to a gene or generegulatory sequence. Commonly used genes for screening presumptivelytransformed cells include α-glucuronidase (GUS), α-galactosidase,luciferase, chloramphenicol, and acetyltransferase (Jefferson, R. A.,Plant Mol. Biol. Rep. 5:387 (1987), Teeri et al., EMBO J. 8:343 (1989),Koncz et al., Proc. Natl. Acad. Sci. U.S.A. 84:131 (1987), DeBlock etal., EMBO J. 3:1681 (1984)).

In vivo methods for visualizing GUS activity that do not requiredestruction of plant tissues are available (Molecular Probes publication2908, IMAGENE GREEN, p. 1-4 (1993) and Naleway et al., J. Cell Biol.115:151a (1991)). However, these in vivo methods for visualizing GUSactivity have not proven useful for recovery of transformed cellsbecause of low sensitivity, high fluorescent backgrounds and limitationsassociated with the use of luciferase genes as selectable markers.

More recently, a gene encoding Green Fluorescent Protein (GFP) has beenutilized as a marker for gene expression in prokaryotic and eukaryoticcells (Chalfie et al., Science 263:802 (1994)). GFP and mutants of GFPmay be used as screenable markers.

Expression Vectors for Celery Transformation: Promoters

Genes included in expression vectors must be driven by a nucleotidesequence comprising a regulatory element, such as a promoter. Severaltypes of promoters are now well known in the arts, as are otherregulatory elements that can be used alone or in combination withpromoters.

As used herein, “promoter” includes reference to a region of DNAupstream from the start of transcription and involved in recognition andbinding of RNA polymerase and other proteins to initiate transcription.A “plant promoter” is a promoter capable of initiating transcription inplant cells. Examples of promoters under developmental control includethose which preferentially initiate transcription in certain tissues,such as leaves, roots, seeds, fibers, xylem vessels, tracheids, orsclerenchyma. These promoters are referred to as “tissue-preferred”.Promoters which initiate transcription only in certain tissue arereferred to as “tissue-specific”. A “cell type” specific promoterprimarily drives expression in certain cell types in one or more organs,for example, vascular cells in roots or leaves. An “inducible” promoteris a promoter which is under environmental control. Examples ofenvironmental conditions that may effect transcription by induciblepromoters include anaerobic conditions or the presence of light.Tissue-specific, tissue-preferred, cell type specific, and induciblepromoters constitute the class of “non-constitutive” promoters. A“constitutive” promoter is a promoter which is active under mostenvironmental conditions.

A. Inducible Promoters

An inducible promoter is operably linked to a gene for expression incelery. Optionally, the inducible promoter is operably linked to anucleotide sequence encoding a signal sequence which is operably linkedto a gene for expression in celery. With an inducible promoter the rateof transcription increases in response to an inducing agent.

Any inducible promoter can be used in the instant invention. See Ward etal., Plant Mol. Biol. 22:361-366 (1993). Exemplary inducible promotersinclude, but are not limited to, that from the ACEI system whichresponds to copper (Meft et al., PNAS 90:4567-4571 (1993)); In2 genefrom maize which responds to benzenesulfonamide herbicide safeners(Hershey et al., Mol. Gen. Genetics 227:229-237 (1991) and Gatz et al.,Mol. Gen. Genetics 243:32-38 (1994)) or Tet repressor from Tn10 (Gatz etal., Mol. Gen. Genetics 227:229-237 (1991). A particularly preferredinducible promoter is a promoter that responds to an inducing agent towhich plants do not normally respond. An exemplary inducible promoter isthe inducible promoter from a steroid hormone gene, the transcriptionalactivity of which is induced by a glucocorticosteroid hormone. Schena etal., Proc. Natl. Acad. Sci. U.S.A. 88:0421 (1991).

B. Constitutive Promoters

A constitutive promoter is operably linked to a gene for expression incelery or the constitutive promoter is operably linked to a nucleotidesequence encoding a signal sequence which is operably linked to a genefor expression in celery.

Many different constitutive promoters can be utilized in the instantinvention. Exemplary constitutive promoters include, but are not limitedto, the promoters from plant viruses such as the 35S promoter from CaMV(Odell et al., Nature 313:810-812 (1985) and the promoters from suchgenes as rice actin (McElroy et al., Plant Cell 2:163-171 (1990));ubiquitin (Christensen et al., Plant Mol. Biol. 12:619-632 (1989) andChristensen et al., Plant Mol. Biol. 18:675-689 (1992)); pEMU (Last etal., Theor. Appl. Genet. 81:581-588 (1991)); MAS (Velten et al., EMBO J.3:2723-2730 (1984)) and maize H3 histone (Lepetit et al., Mol. Gen.Genetics 231:276-285 (1992) and Atanassova et al., Plant Journal 2 (3):291-300 (1992)). The ALS promoter, Xbal/Ncol fragment 5′ to the Brassicanapus ALS3 structural gene (or a nucleotide sequence similarity to saidXbal/Ncol fragment), represents a particularly useful constitutivepromoter. See PCT application WO 96/30530.

C. Tissue-Specific or Tissue-Preferred Promoters

A tissue-specific promoter is operably linked to a gene for expressionin celery. Optionally, the tissue-specific promoter is operably linkedto a nucleotide sequence encoding a signal sequence which is operablylinked to a gene for expression in celery. Plants transformed with agene of interest operably linked to a tissue-specific promoter producethe protein product of the transgene exclusively, or preferentially, ina specific tissue.

Any tissue-specific or tissue-preferred promoter can be utilized in theinstant invention. Exemplary tissue-specific or tissue-preferredpromoters include, but are not limited to, a root-preferred promoter,such as that from the phaseolin gene (Murai et al., Science 23:476-482(1983) and Sengupta-Gopalan et al., Proc. Natl. Acad. Sci. U.S.A.82:3320-3324 (1985)); a leaf-specific and light-induced promoter such asthat from cab or rubisco (Simpson et al., EMBO J. 4(11):2723-2729 (1985)and Timko et al., Nature 318:579-582 (1985)); an anther-specificpromoter such as that from LAT52 (Twell et al., Mol. Gen. Genetics217:240-245 (1989)); a pollen-specific promoter such as that from Zml3(Guerrero et al., Mol. Gen. Genetics 244:161-168 (1993)) or amicrospore-preferred promoter such as that from apg (Twell et al., Sex.Plant Reprod. 6:217-224 (1993)).

Signal Sequences for Targeting Proteins to Subcellular Compartments

Transport of protein produced by transgenes to a subcellular compartmentsuch as the chloroplast, vacuole, peroxisome, glyoxysome, cell wall ormitochondrion or for secretion into the apoplast, is accomplished bymeans of operably linking the nucleotide sequence encoding a signalsequence to the 5′ and/or 3′ region of a gene encoding the protein ofinterest. Targeting sequences at the 5′ and/or 3′ end of the structuralgene may determine, during protein synthesis and processing, where theencoded protein is ultimately compartmentalized.

The presence of a signal sequence directs a polypeptide to either anintracellular organelle or subcellular compartment or for secretion tothe apoplast. Many signal sequences are known in the art; for example,Becker et al., Plant Mol. Biol. 20:49 (1992), Close, P. S., Master'sThesis, Iowa State University (1993), Knox, C., et al., A Structure andOrganization of Two Divergent Alpha-Amylase Genes from Barley”, PlantMol. Biol. 9:3-17 (1987), Lerner et al., Plant Physiol. 91:124-129(1989), Fontes et al., Plant Cell 3:483-496 (1991), Matsuoka et al.,Proc. Natl. Acad. Sci. 88:834 (1991), Gould et al., J. Cell. Biol.108:1657 (1989), Creissen et al., Plant J. 2:129 (1991), Kalderon, etal., A short amino acid sequence able to specify nuclear location, Cell39:499-509 (1984), Steifel, et al., Expression of a maize cell wallhydroxyproline-rich glycoprotein gene in early leaf and root vasculardifferentiation, Plant Cell 2:785-793 (1990).

Foreign Protein Genes and Agronomic Genes

With transgenic plants according to the present invention, a foreignprotein can be produced in commercial quantities. Thus, techniques forthe selection and propagation of transformed plants, which are wellunderstood in the art, yield a plurality of transgenic plants which areharvested in a conventional manner, and a foreign protein can then beextracted from a tissue of interest or from total biomass. Proteinextraction from plant biomass can be accomplished by known methods whichare discussed, for example, by Heney and Orr, Anal. Biochem. 114:92-6(1981).

According to a preferred embodiment, the transgenic plant provided forcommercial production of foreign protein is celery. In another preferredembodiment, the biomass of interest is seed. For the relatively smallnumber of transgenic plants that show higher levels of expression, agenetic map can be generated, primarily via conventional RFLP, PCR andSSR analysis, which identifies the approximate chromosomal location ofthe integrated DNA molecule. For exemplary methodologies in this regard,see Glick and Thompson, Methods in Plant Molecular Biology andBiotechnology, CRC Press, Boca Raton 269:284 (1993). Map informationconcerning chromosomal location is useful for proprietary protection ofa subject transgenic plant. If unauthorized propagation is undertakenand crosses made with other germplasm, the map of the integration regioncan be compared to similar maps for suspect plants, to determine if thelatter have a common parentage with the subject plant. Map comparisonswould involve hybridizations, RFLP, PCR, SSR and sequencing, all ofwhich are conventional techniques.

Likewise, by means of the present invention, agronomic genes can beexpressed in transformed plants. More particularly, plants can begenetically engineered to express various phenotypes of agronomicinterest. Exemplary genes implicated in this regard include, but are notlimited to, those categorized below:

1. Genes that Confer Resistance to Pests or Disease and that Encode:

A. Plant disease resistance genes. Plant defenses are often activated byspecific interaction between the product of a disease resistance gene(R) in the plant and the product of a corresponding avirulence (Avr)gene in the pathogen. A plant line can be transformed with a clonedresistance gene to engineer plants that are resistant to specificpathogen strains. See, for example Jones et al., Science 266:789 (1994)(cloning of the tomato Cf-9 gene for resistance to Cladosporium fulvum);Martin et al., Science 262:1432 (1993) (tomato Pto gene for resistanceto Pseudomonas syringae pv. tomato encodes a protein kinase); Mindrinoset al., Cell 78:1089 (1994) (Arabidopsis RSP2 gene for resistance toPseudomonas syringae).

B. A Bacillus thuringiensis protein, a derivative thereof or a syntheticpolypeptide modeled thereon. See, for example, Geiser et al., Gene48:109 (1986), who disclose the cloning and nucleotide sequence of a Btδ-endotoxin gene. Moreover, DNA molecules encoding δ-endotoxin genes canbe purchased from American Type Culture Collection, Manassas, Va., underATCC Accession Nos. 40098, 67136, 31995 and 31998.

C. A lectin. See, for example, the disclosure by Van Damme et al., PlantMolec. Biol. 24:25 (1994), who disclose the nucleotide sequences ofseveral Clivia miniata mannose-binding lectin genes.

D. A vitamin-binding protein such as avidin. See PCT application US93/06487, the contents of which are hereby incorporated by reference.The application teaches the use of avidin and avidin homologues aslarvicides against insect pests.

E. An enzyme inhibitor, for example, a protease or proteinase inhibitoror an amylase inhibitor. See, for example, Abe et al., J. Biol. Chem.262:16793 (1987) (nucleotide sequence of rice cysteine proteinaseinhibitor), Huub et al., Plant Molec. Biol. 21:985 (1993) (nucleotidesequence of cDNA encoding tobacco proteinase inhibitor I), Sumitani etal., Biosci. Biotech. Biochem. 57:1243 (1993) (nucleotide sequence ofStreptomyces nitrosporeus α-amylase inhibitor).

F. An insect-specific hormone or pheromone such as an ecdysteroid andjuvenile hormone, a variant thereof, a mimetic based thereon, or anantagonist or agonist thereof. See, for example, the disclosure byHammock et al., Nature 344:458 (1990), of baculovirus expression ofcloned juvenile hormone esterase, an inactivator of juvenile hormone.

G. An insect-specific peptide or neuropeptide which, upon expression,disrupts the physiology of the affected pest. For example, see thedisclosures of Regan, J. Biol. Chem. 269:9 (1994) (expression cloningyields DNA coding for insect diuretic hormone receptor), and Pratt etal., Biochem. Biophys. Res. Comm. 163:1243 (1989) (an allostatin isidentified in Diploptera puntata). See also U.S. Pat. No. 5,266,317 toTomalski et al., who disclose genes encoding insect-specific, paralyticneurotoxins.

H. An insect-specific venom produced in nature by a snake, a wasp, etc.For example, see Pang et al., Gene 116:165 (1992), for disclosure ofheterologous expression in plants of a gene coding for a scorpioninsectotoxic peptide.

I. An enzyme responsible for a hyperaccumulation of a monoterpene, asesquiterpene, a steroid, hydroxamic acid, a phenylpropanoid derivativeor another non-protein molecule with insecticidal activity.

J. An enzyme involved in the modification, including thepost-translational modification, of a biologically active molecule; forexample, a glycolytic enzyme, a proteolytic enzyme, a lipolytic enzyme,a nuclease, a cyclase, a transaminase, an esterase, a hydrolase, aphosphatase, a kinase, a phosphorylase, a polymerase, an elastase, achitinase and a glucanase, whether natural or synthetic. See PCTapplication WO 93/02197 in the name of Scott et al., which discloses thenucleotide sequence of a callase gene. DNA molecules which containchitinase-encoding sequences can be obtained from ATCC Accession Nos.39637 and 67152. See also Kramer et al., Insect Biochem. Molec. Biol.23:691 (1993), who teach the nucleotide sequence of a cDNA encodingtobacco hornworm chitinase, and Kawalleck et al., Plant Molec. Biol.21:673 (1993), who provide the nucleotide sequence of the parsley ubi4-2polyubiquitin gene.

K. A molecule that stimulates signal transduction. For example, see thedisclosure by Botella et al., Plant Molec. Biol, 24:757 (1994), ofnucleotide sequences for mung bean calmodulin cDNA clones, and Griess etal., Plant Physiol. 104:1467 (1994), who provide the nucleotide sequenceof a maize calmodulin cDNA clone.

L. A hydrophobic moment peptide. See PCT application WO 95/16776(disclosure of peptide derivatives of tachyplesin which inhibit fungalplant pathogens) and PCT application WO 95/18855 (teaches syntheticantimicrobial peptides that confer disease resistance), the respectivecontents of which are hereby incorporated by reference.

M. A membrane permease, a channel former or a channel blocker. Forexample, see the disclosure of Jaynes et al., Plant Sci 89:43 (1993), ofheterologous expression of a cecropin-β, lytic peptide analog to rendertransgenic tobacco plants resistant to Pseudomonas solanacearum.

N. A viral-invasive protein or a complex toxin derived therefrom. Forexample, the accumulation of viral coat proteins in transformed plantcells imparts resistance to viral infection and/or disease developmenteffected by the virus from which the coat protein gene is derived, aswell as by related viruses. See Beachy et al., Ann. rev. Phytopathol.28:451 (1990). Coat protein-mediated resistance has been conferred upontransformed plants against alfalfa mosaic virus, cucumber mosaic virus,tobacco streak virus, potato virus X, potato virus Y, tobacco etchvirus, tobacco rattle virus and tobacco mosaic virus.

O. An insect-specific antibody or an immunotoxin derived there from.Thus, an antibody targeted to a critical metabolic function in theinsect gut would inactivate an affected enzyme, killing the insect(Taylor et al., Abstract #497, Seventh Int'l Symposium on MolecularPlant-Microbe Interactions (Edinburgh, Scotland) (1994) (enzymaticinactivation in transgenic tobacco via production of single-chainantibody fragments)).

P. A virus-specific antibody. For example, Tavladoraki et al., Nature366:469 (1993), shows that transgenic plants expressing recombinantantibody genes are protected from virus attack.

Q. A developmental-arrestive protein produced in nature by a pathogen ora parasite. Thus, fungal endo-α-1,4-D-polygalacturonases facilitatefungal colonization and plant nutrient release by solubilizing plantcell wall homo-α-1,4-D-galacturonase. See Lamb et al., Bio/Technology10:1436 (1992). The cloning and characterization of a gene which encodesa bean endopolygalacturonase-inhibiting protein is described by Toubartet al., Plant J. 2:367 (1992).

R. A developmental-arrestive protein produced in nature by a plant. Forexample, Logemann et al., Bio/Technology 10:305 (1992), have shown thattransgenic plants expressing the barley ribosome-inactivating gene havean increased resistance to fungal disease.

S. A lettuce mosaic potyvirus (LMV) coat protein gene introduced intoLactuca sativa in order to increase its resistance to LMV infection. SeeDinant et al., Molecular Breeding. 1997, 3: 1, 75-86.

2. Genes that Confer Resistance to an Herbicide:

A. An herbicide that inhibits the growing point or meristem, such as animidazolinone or a sulfonylurea. Exemplary genes in this category codefor mutant ALS and AHAS enzyme as described, for example, by Lee et al.,EMBO J. 7:1241 (1988), and Miki et al., Theor. Appl. Genet. 80:449(1990), respectively.

B. Glyphosate (resistance conferred by mutant5-enolpyruvlshikimate-3-phosphate synthase (EPSPS) and aroA genes,respectively) and other phosphono compounds such as glufosinate(phosphinothricin acetyl transferase (PAT) and Streptomyceshygroscopicus PAT bar genes), and pyridinoxy or phenoxy proprionic acidsand cyclohexones (ACCase inhibitor-encoding genes). See, for example,U.S. Pat. No. 4,940,835 to Shah, et al., which discloses the nucleotidesequence of a form of EPSPS which can confer glyphosate resistance. ADNA molecule encoding a mutant aroA gene can be obtained under ATCCaccession number 39256, and the nucleotide sequence of the mutant geneis disclosed in U.S. Pat. No. 4,769,061 to Comai. See alsoUmaballava-Mobapathie in Transgenic Research. 1999, 8: 1, 33-44 thatdiscloses Lactuca sativa resistant to glufosinate. European PatentApplication No. 0 333 033 to Kumada et al., and U.S. Pat. No. 4,975,374to Goodman et al., disclose nucleotide sequences of glutamine synthetasegenes which confer resistance to herbicides such as L-phosphinothricin.The nucleotide sequence of a phosphinothricin-acetyl-transferase gene isprovided in European Patent Application No. 0 242 246 to Leemans et al.DeGreef et al., Bio/Technology 7:61 (1989), describe the production oftransgenic plants that express chimeric bar genes coding forphosphinothricin acetyl transferase activity. Examples of genesconferring resistance to phenoxy proprionic acids and cyclohexones, suchas sethoxydim and haloxyfop are the Accl-S1, Accl-S2 and Accl-S3 genesdescribed by Marshall et al., Theor. Appl. Genet. 83:435 (1992).

C. An herbicide that inhibits photosynthesis, such as a triazine (psbAand gs+genes) and a benzonitrile (nitrilase gene). Przibilla et al.,Plant Cell 3:169 (1991), describe the transformation of Chlamydomonaswith plasmids encoding mutant psbA genes. Nucleotide sequences fornitrilase genes are disclosed in U.S. Pat. No. 4,810,648 to Stalker, andDNA molecules containing these genes are available under ATCC AccessionNos. 53435, 67441, and 67442. Cloning and expression of DNA coding for aglutathione S-transferase is described by Hayes et al., Biochem. J.285:173 (1992).

D. Acetohydroxy acid synthase, which has been found to make plants thatexpress this enzyme resistant to multiple types of herbicides, has beenintroduced into a variety of plants. See Hattori et al., Mol. Gen.Genet. 246:419, 1995. Other genes that confer tolerance to herbicidesinclude a gene encoding a chimeric protein of rat cytochrome P4507A1 andyeast NADPH-cytochrome P450 oxidoreductase (Shiota et al., PlantPhysiol., 106:17, 1994), genes for glutathione reductase and superoxidedismutase (Aono et al., Plant Cell Physiol. 36:1687, 1995), and genesfor various phosphotransferases (Datta et al., Plant Mol. Biol. 20:619,1992).

E. Protoporphyrinogen oxidase (protox) is necessary for the productionof chlorophyll, which is necessary for all plant survival. The protoxenzyme serves as the target for a variety of herbicidal compounds. Theseherbicides also inhibit growth of all the different species of plantspresent, causing their total destruction. The development of plantscontaining altered protox activity which are resistant to theseherbicides are described in U.S. Pat. Nos. 6,288,306; 6,282,837;5,767,373; and international publication WO 01/12825.

F. Modified bolting tolerance in plants for example, by transferring agene encoding for gibberellin 2-oxidase (U.S. Pat. No. 7,262,340).Bolting has also been modified using non-transformation methods; seeWittwer, S. H., et al. (1957) Science. 126(3262): 30-31; Booij, R. etal., (1995) Scientia Horticulturae. 63:143-154; and Booij, R. et al.,(1994) Scientia Horticulturae. 58:271-282.

3. Genes that Confer or Contribute to a Value-Added Trait, Such as:

A. Increased iron content of the celery, for example by transforming aplant with a soybean ferritin gene as described in Goto et al., ActaHorticulturae. 2000, 521, 101-109.

B. Decreased nitrate content of leaves, for example by transforming acelery with a gene coding for a nitrate reductase. See for exampleCurtis et al., Plant Cell Report. 1999, 18: 11, 889-896.

C. Increased sweetness of the celery by transferring a gene coding formonellin, that elicits a flavor 100,000 times sweeter than sugar on amolar basis. See Penarrubia et al., Biotechnology. 1992, 10: 561-564.

D. Modified fatty acid metabolism, for example, by transforming a plantwith an antisense gene of stearyl-ACP desaturase to increase stearicacid content of the plant. See Knultzon et al., Proc. Natl. Acad. Sci.USA 89:2625 (1992).

E. Modified carbohydrate composition effected, for example, bytransforming plants with a gene coding for an enzyme that alters thebranching pattern of starch. See Shiroza et al., J. Bacteriol. 170:810(1988) (nucleotide sequence of Streptococcus mutantsfructosyltransferase gene), Steinmetz et al., Mol. Gen. Genet. 20:220(1985) (nucleotide sequence of Bacillus subtilis levansucrase gene), Penet al., Bio/Technology 10:292 (1992) (production of transgenic plantsthat express Bacillus lichenifonnis α-amylase), Elliot et al., PlantMolec. Biol. 21:515 (1993) (nucleotide sequences of tomato invertasegenes), SOgaard et al., J. Biol. Chem. 268:22480 (1993) (site-directedmutagenesis of barley α-amylase gene), and Fisher et al., Plant Physiol.102:1045 (1993) (maize endosperm starch branching enzyme II).

4. Genes that Control Male-Sterility

A. Introduction of a deacetylase gene under the control of atapetum-specific promoter and with the application of the chemicalN-Ac-PPT; see international publication WO 01/29237.

B. Introduction of various stamen-specific promoters; see internationalpublications WO 92/13956 and WO 92/13957.

C. Introduction of the barnase and the barstar genes; see Paul et al.,Plant Mol. Biol. 19:611-622, 1992).

Methods for Celery Transformation

Numerous methods for plant transformation have been developed, includingbiological and physical, plant transformation protocols. See, forexample, Miki et al., “Procedures for Introducing Foreign DNA intoPlants” in Methods in Plant Molecular Biology and Biotechnology, GlickB. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993) pages67-88. In addition, expression vectors and in vitro culture methods forplant cell or tissue transformation and regeneration of plants areavailable. See, for example, Gruber et al., “Vectors for PlantTransformation” in Methods in Plant Molecular Biology and Biotechnology,Glick B. R. and Thompson, J. E. Eds. (CRC Press, Inc., Boca Raton, 1993)pages 89-119.

A. Agrobacterium-Mediated Transformation

One method for introducing an expression vector into plants is based onthe natural transformation system of Agrobacterium. See, for example,Horsch et al., Science 227:1229 (1985), Curtis et al., Journal ofExperimental Botany. 1994, 45: 279, 1441-1449, Torres et al., Plant cellTissue and Organic Culture. 1993, 34: 3, 279-285, Dinant et al.,Molecular Breeding. 1997, 3: 1, 75-86. A. tumefaciens and A. rhizogenesare plant pathogenic soil bacteria which genetically transform plantcells. The Ti and Ri plasmids of A. tumefaciens and A. rhizogenes,respectively, carry genes responsible for genetic transformation of theplant. See, for example, Kado, C. I., Crit. Rev. Plant Sci. 10:1 (1991).Descriptions of Agrobacterium vector systems and methods forAgrobacterium-mediated gene transfer are provided by Gruber et al.,supra, Miki et al., supra, and Moloney et al., Plant Cell Reports 8:238(1989). See also, U.S. Pat. No. 5,591,616 issued Jan. 7, 1997.

B. Direct Gene Transfer

Several methods of plant transformation collectively referred to asdirect gene transfer, have been developed as an alternative toAgrobacterium-mediated transformation. A generally applicable method ofplant transformation is microprojectile-mediated transformation whereinDNA is carried on the surface of microprojectiles measuring 1 to 4 μm.The expression vector is introduced into plant tissues with a biolisticdevice that accelerates the microprojectiles to speeds of 300 to 600 m/swhich is sufficient to penetrate plant cell walls and membranes.Russell, D. R., et al. Pl. Cell. Rep. 12(3, Jan.), 165-169 (1993),Aragao, F. J. L., et al. Plant Mol. Biol. 20(2, Oct.), 357-359 (1992),Aragao, F. J. L., et al. Pl. Cell. Rep. 12(9, July), 483-490 (1993).Aragao, Theor. Appl. Genet. 93: 142-150 (1996), Kim, J.; Minamikawa, T.Plant Science 117: 131-138 (1996), Sanford et al., Part. Sci. Technol.5:27 (1987), Sanford, J. C., Trends Biotech. 6:299 (1988), Klein et al.,Bio/Technology 6:559-563 (1988), Sanford, J. C., Physiol Plant 7:206(1990), Klein et al., Biotechnology 10:268 (1992).

Another method for physical delivery of DNA to plants is sonication oftarget cells. Zhang et al., Bio/Technology 9:996 (1991). Alternatively,liposome and spheroplast fusion have been used to introduce expressionvectors into plants. Deshayes et al., EMBO J., 4:2731 (1985), Christouet al., Proc Natl. Acad. Sci. U.S.A. 84:3962 (1987). Direct uptake ofDNA into protoplasts using CaCl₂ precipitation, polyvinyl alcohol orpoly-L-ornithine have also been reported. Hain et al., Mol. Gen. Genet.199:161 (1985) and Draper et al., Plant Cell Physiol. 23:451 (1982).Electroporation of protoplasts and whole cells and tissues have alsobeen described. Saker, M.; Kuhne, T. Biologia Plantarum 40(4): 507-514(1997/98), Donn et al., In Abstracts of VIIth International Congress onPlant Cell and Tissue Culture IAPTC, A2-38, p 53 (1990); D'Halluin etal., Plant Cell 4:1495-1505 (1992) and Spencer et al., Plant Mol. Biol.24:51-61 (1994). See also Chupean et al., Biotechnology. 1989, 7: 5,503-508.

Following transformation of celery target tissues, expression of theabove-described selectable marker genes allows for preferentialselection of transformed cells, tissues and/or plants, usingregeneration and selection methods now well known in the art.

The foregoing methods for transformation would typically be used forproducing a transgenic line. The transgenic line could then be crossed,with another (non-transformed or transformed) line, in order to producea new transgenic celery line. Alternatively, a genetic trait which hasbeen engineered into a particular celery cultivar using the foregoingtransformation techniques could be moved into another line usingtraditional backcrossing techniques that are well known in the plantbreeding arts. For example, a backcrossing approach could be used tomove an engineered trait from a public, non-elite inbred line into anelite inbred line, or from an inbred line containing a foreign gene inits genome into an inbred line or lines which do not contain that gene.As used herein, “crossing” can refer to a simple X by Y cross, or theprocess of backcrossing, depending on the context.

Single-Gene Conversions

When the term celery plant, cultivar or celery line is used in thecontext of the present invention, this also includes any single geneconversions of that line. The term “single gene converted plant” as usedherein refers to those celery plants which are developed by a plantbreeding technique called backcrossing wherein essentially all of thedesired morphological and physiological characteristics of a cultivarare recovered in addition to the single gene transferred into the linevia the backcrossing technique. Backcrossing methods can be used withthe present invention to improve or introduce a characteristic into theline. The term “backcrossing” as used herein refers to the repeatedcrossing of a hybrid progeny back to one of the parental celery plantsfor that line, backcrossing 1, 2, 3, 4, 5, 6, 7, 8 or more times to therecurrent parent. The parental celery plant which contributes the genefor the desired characteristic is termed the nonrecurrent or donorparent. This terminology refers to the fact that the nonrecurrent parentis used one time in the backcross protocol and therefore does not recur.The parental celery plant to which the gene or genes from thenonrecurrent parent are transferred is known as the recurrent parent asit is used for several rounds in the backcrossing protocol (Poehlman &Sleper, 1994; Fehr, 1987). In a typical backcross protocol, the originalcultivar of interest (recurrent parent) is crossed to a second line(nonrecurrent parent) that carries the single gene of interest to betransferred. The resulting progeny from this cross are then crossedagain to the recurrent parent and the process is repeated until a celeryplant is obtained wherein essentially all of the desired morphologicaland physiological characteristics of the recurrent parent are recoveredin the converted plant, in addition to the single transferred gene fromthe nonrecurrent parent.

The selection of a suitable recurrent parent is an important step for asuccessful backcrossing procedure. The goal of a backcross protocol isto alter or substitute a single trait or characteristic in the originalline. To accomplish this, a single gene of the recurrent cultivar ismodified or substituted with the desired gene from the nonrecurrentparent, while retaining essentially all of the rest of the desiredgenetic, and therefore the desired physiological and morphological,constitution of the original line. The choice of the particularnonrecurrent parent will depend on the purpose of the backcross, one ofthe major purposes is to add some commercially desirable, agronomicallyimportant trait to the plant. The exact backcrossing protocol willdepend on the characteristic or trait being altered to determine anappropriate testing protocol. Although backcrossing methods aresimplified when the characteristic being transferred is a dominantallele, a recessive allele may also be transferred. In this instance itmay be necessary to introduce a test of the progeny to determine if thedesired characteristic has been successfully transferred.

Many single gene traits have been identified that are not regularlyselected for in the development of a new line but that can be improvedby backcrossing techniques. Single gene traits may or may not betransgenic, examples of these traits include but are not limited to,male sterility, modified fatty acid metabolism, modified carbohydratemetabolism, herbicide resistance, resistance for bacterial, fungal, orviral disease, insect resistance, enhanced nutritional quality,industrial usage, yield stability and yield enhancement. These genes aregenerally inherited through the nucleus. Several of these single genetraits are described in U.S. Pat. Nos. 5,777,196, 5,948,957 and5,969,212, the disclosures of which are specifically hereby incorporatedby reference.

Tissue Culture

Further reproduction of the variety can occur by tissue culture andregeneration. Tissue culture of various tissues of celery andregeneration of plants therefrom is well known and widely published. Forexample, reference may be had to Teng et al., HortScience. 1992, 27: 9,1030-1032 Teng et al., HortScience. 1993, 28: 6, 669-1671, Zhang et al.,Journal of Genetics and Breeding. 1992, 46: 3, 287-290, Webb et al.,Plant Cell Tissue and Organ Culture. 1994, 38: 1, 77-79, Curtis et al.,Journal of Experimental Botany. 1994, 45: 279, 1441-1449, Nagata et al.,Journal for the American Society for Horticultural Science. 2000, 125:6, 669-672, and Ibrahim et al., Plant Cell, Tissue and Organ Culture.(1992), 28(2): 139-145. It is clear from the literature that the stateof the art is such that these methods of obtaining plants are routinelyused and have a very high rate of success. Thus, another aspect of thisinvention is to provide cells which upon growth and differentiationproduce celery plants having the physiological and morphologicalcharacteristics of variety ADS-20.

As used herein, the term “tissue culture” indicates a compositioncomprising isolated cells of the same or a different type or acollection of such cells organized into parts of a plant. Exemplarytypes of tissue cultures are protoplasts, calli, meristematic cells, andplant cells that can generate tissue culture that are intact in plantsor parts of plants, such as leaves, pollen, embryos, roots, root tips,anthers, pistils, flowers, seeds, petioles, suckers and the like. Meansfor preparing and maintaining plant tissue culture are well known in theart. By way of example, a tissue culture comprising organs has been usedto produce regenerated plants. U.S. Pat. Nos. 5,959,185, 5,973,234 and5,977,445 describe certain techniques, the disclosures of which areincorporated herein by reference.

Additional Breeding Methods

This invention also is directed to methods for producing a celery plantby crossing a first parent celery plant with a second parent celeryplant wherein the first or second parent celery plant is a celery plantof cultivar ADS-20. Further, both first and second parent celery plantscan come from celery cultivar ADS-20. Thus, any breeding methods usingcelery cultivar ADS-20 are part of this invention, such as selling,backcrosses, hybrid production, crosses to populations, and the like.All plants produced using celery cultivar ADS-20 as at least one parentare within the scope of this invention, including those developed fromcultivars derived from celery cultivar ADS-20. Advantageously, thiscelery cultivar could be used in crosses with other, different, celeryplants to produce the first generation (F₁) celery hybrid seeds andplants with superior characteristics. The cultivar of the invention canalso be used for transformation where exogenous genes are introduced andexpressed by the cultivar of the invention. Genetic variants createdeither through traditional breeding methods using celery cultivar ADS-20or through transformation of cultivar ADS-20 by any of a number ofprotocols known to those of skill in the art are intended to be withinthe scope of this invention.

The following describes breeding methods that may be used with celerycultivar ADS-20 in the development of further celery plants. One suchembodiment is a method for developing cultivar ADS-20 progeny celeryplants in a celery plant breeding program comprising: obtaining thecelery plant, or a part thereof, of cultivar ADS-20 utilizing said plantor plant part as a source of breeding material, and selecting a celerycultivar ADS-20 progeny plant with molecular markers in common withcultivar ADS-20 and/or with morphological and/or physiologicalcharacteristics selected from the characteristics listed in Table 1.Breeding steps that may be used in the celery plant breeding programinclude pedigree breeding, backcrossing, mutation breeding, andrecurrent selection. In conjunction with these steps, techniques such asRFLP-enhanced selection, genetic marker enhanced selection (for exampleSSR markers) and the making of double haploids may be utilized.

Another method involves producing a population of celery cultivar ADS-20progeny celery plants, comprising crossing cultivar ADS-20 with anothercelery plant, thereby producing a population of celery plants, which, onaverage, derive 50% of their alleles from celery cultivar ADS-20. Aplant of this population may be selected and repeatedly selfed or sibbedwith a celery cultivar resulting from these successive filialgenerations. One embodiment of this invention is the celery cultivarproduced by this method and that has obtained at least 50% of itsalleles from celery cultivar ADS-20.

One of ordinary skill in the art of plant breeding would know how toevaluate the traits of two plant varieties to determine if there is nosignificant difference between the two traits expressed by thosevarieties. For example, see Fehr and Walt, Principles of CultivarDevelopment, p 261-286 (1987). Thus the invention includes celerycultivar ADS-20 progeny celery plants comprising a combination of atleast two cultivar ADS-20 traits selected from the group consisting ofthose listed in Table 1 or the cultivar ADS-20 combination of traitslisted in the Summary of the Invention, so that said progeny celeryplant is not significantly different for said traits than celerycultivar ADS-20 as determined at the 5% significance level when grown inthe same environmental conditions. Using techniques described herein,molecular markers may be used to identify said progeny plant as a celerycultivar ADS-20 progeny plant. Mean trait values may be used todetermine whether trait differences are significant, and preferably thetraits are measured on plants grown under the same environmentalconditions. Once such a variety is developed its value is substantialsince it is important to advance the germplasm base as a whole in orderto maintain or improve traits such as yield, disease resistance, pestresistance, and plant performance in extreme environmental conditions.

Progeny of celery cultivar ADS-20 may also be characterized throughtheir filial relationship with celery cultivar ADS-20, as for example,being within a certain number of breeding crosses of celery cultivarADS-20. A breeding cross is a cross made to introduce new genetics intothe progeny, and is distinguished from a cross, such as a self or a sibcross, made to select among existing genetic alleles. The lower thenumber of breeding crosses in the pedigree, the closer the relationshipbetween celery cultivar ADS-20 and its progeny. For example, progenyproduced by the methods described herein may be within 1, 2, 3, 4 or 5breeding crosses of celery cultivar ADS-20.

As used herein, the term “plant” includes plant cells, plantprotoplasts, plant cell tissue cultures from which celery plants can beregenerated, plant calli, plant clumps and plant cells that are intactin plants or parts of plants, such as leaves, pollen, embryos, roots,root tips, anthers, pistils, flowers, seeds, petioles, suckers and thelike.

Industrial Uses of Celery Cultivar ADS-20

Celery may be used in a variety of manner including but not limited to,use in salads, soups, being filled with cheese, soybean, vegetable,peanut butter or dairy type products, served raw, cooked, baked orfrozen, served as sticks, pieces, dices, or dipped like potato chips.

TABLES

In the tables that follow, the traits and characteristics of celerycultivar ADS-20 are given compared to other cultivars.

Tables 2-5 compare field harvest yields between celery cultivar ADS-20and celery cultivar Hill's Special on four different planting datesgrown in relative proximity of one another in Oxnard, Calif. Data wastaken in April 2010 from a total plant population of 52,800 plants peracre.

TABLE 2 Characteristic ADS-20 Hill's Special Harvest Date Apr. 16, 2010Apr. 6, 2010 Plant Population 52,800 52,800 Maturity Days 135 125 TotalAcres Harvested 3.5 1.5 Total Cartons Harvested 6,318 2,268 Yield inCartons per acre 1,805 1,512

TABLE 3 Characteristic ADS-20 Hill's Special Harvest Date Apr. 20, 2010Apr. 14, 2010 Plant Population 52,800 52,800 Maturity Days 135 129 TotalAcres Harvested 4.1 1.3 Total Cartons Harvested 7,515 1,994 Yield inCartons per acre 1,833 1,534

TABLE 4 Characteristic ADS-20 Hill's Special Harvest Date Apr. 26, 2010Apr. 16, 2010 Plant Population 52,800 52,800 Maturity Days 126 116 TotalAcres Harvested 7 2 Total Cartons Harvested 11,662 2,900 Yield inCartons per acre 1,666 1,450

TABLE 5 Characteristic ADS-20 Hill's Special Harvest Date Apr. 31, 2010Apr. 22, 2010 Plant Population 52,800 52,800 Maturity Days 132 123 TotalAcres Harvested 7.5 2.5 Total Cartons Harvested 13,058 3,500 Yield inCartons per acre 1,741 1,400

As shown in Tables 2-5, compared to Hill's Special, ADS-20 required 6-10days additional production time to reach similar maturity, but outyielded Hill's Special by 15-20%. Production occurred in the boltingwindow.

Table 6 shows a comparison between cultivars ADS-20, Hill's Special andseveral other cultivars in different trials grown in the prominentbolting windows of 2005, 2006, 2007, 2008, 2009 and 2010. The trialheader shows the location for each trial, the harvest date and thenumber of hours below 50° F. that the celery was exposed to.Measurements were of the length of the seed stem (cm) for each varietyand the median, average and range are presented for those measurements.Blanks in the data occur where the particular cultivar was not includedin the trial.

TABLE 6 Oxnard, CA Oxnard, CA Oxnard, CA Piru, CA Harvest: Apr. 16, 2005Harvest: May 11, 2006 Harvest: Apr. 28, 2007 Harvest: Apr. 28, 2007 263hours <50° F. 796 hours <50° F. 782 hours <50° F. 1,232 hours <50° F.Med Avg Range Med Avg Range Med Avg Range Med Avg Range ADS-20 0.0 0.00-0 0.0 0.0 0-0  0.0 0.0 0-0 0.0 1.3 0-9 Hill's Special 0.0 0.6 0-8 0.01.4 0-18 0.0 5.4  0-22 0.3 10.4  0-49 Tall Utah 52-70 ‘R’ 23.0 21.816-28 26.0 28.6 14-45  69.0 69.9 41-97 Tall Utah 52-75 9.0 8.6  3-1414.0 16.8 3-37 63.5 63.5 53-71 Conquistador 7.0 6.3 4-8 7.0 8.3 4-1656.5 53.3 30-63 Sonora 4.5 7.9 1-23 45.5 48.4 30-71 48.0 43.3 12-69Command 43.0 43.3 28-56 Challenger 35.0 34.9 23-56 57.0 52.7 40-61Mission ADS-1 7.0 7.6  3-12 9.0 10.5 7-31 34.0 35.5 26-47 48.0 45.225-57 VTR 1330 15.0 15.3 10-23 16.5 15.9 7-23 58.0 56.3 46-60 ADS-1613.0 11.2  2-16 7.5 9.4 2-16 48.0 49.2 38-66 Slowbolting Green #12 25.026.0 13-43 55.5 50.8 37-62 Oxnard, CA Santa Paula, CA Oxnard, CAHarvest: May 1, 2008 Harvest: Apr. 22, 2009 Harvest: May 15, 2010 901hours <50° F. 908 hours <50° F. 835 hours <50° F. Med Avg Range Med AvgRange Med Avg Range ADS-20 0.0 0.0  0-0.5 0.0 0.0 0-0 0.0 0.0 0-0 Hill's Special 0.0 3.2  0-18 0.0 5.1  0-29 0.0 0.0  0-0.5 Tall Utah52-70 ‘R’ 49.0 48.9 39-58 75.5 75.3 70-82 37.5 39.2 26-55  Tall Utah52-75 37.0 37.9 33-47 58.5 58.8 44-73 18.0 19.0 1-42 Conquistador 28.529.3 22-39 59.0 60.8 50-83 Sonora 22.5 22.4 17-31 55.0 50.3 36-56 11.012.5 3-27 Command 25.5 27.1 20-37 Challenger 33.5 36.0 30-48 Mission32.0 31.7 12-53 ADS-1 25.0 24.5 13-38 46.5 45.3 21-67 12.0 13.1 2-35 VTR1330 30.0 29.6 15-45 ADS-16 31.0 30.0 15-36 11.0 13.2 2-31 SlowboltingGreen #12

As shown in Table 6, with the exception of Piru, ADS-20 had essentiallyno measurable seed stem development as measured in cm. Hill's Specialwas slightly less tolerant in all areas except Piru. Pint is a muchcolder production area than all of the other areas (1,232 hours below50° F.). Under the coldest conditions of the Piru production area ADS-20was significantly more tolerant that Hill's Special. Both ADS-20 andHill's Special were significantly more bolting tolerant, as measured byseed stem length, than all other varieties.

Table 7 shows a comparison between cultivars ADS-20, Hill's Special andseveral other cultivars in different trials grown in a field located inOxnard Calif. that has an extremely high level of Fusarium oxysporum f.sp. apii race 2. The field was specially developed with particularlyhigher levels for the purpose of evaluating varieties for Fusariumtolerance. The table presents a comparison between varieties fortolerance to fusarium as measured by the length to the joint in cm and ageneral rating of the celery stalk and in several of the trials a rootdamage rating. All ratings are based on a 0 to 5 scale with 0=death and5=resistant. Ratings may be presented as a range in order todifferentiate the amount of tolerance between stalks in the cultivar.Each trial is differentiated by the evaluation date.

TABLE 7 Jun. 21, 2001 Dec. 1, 2008 Jun. 25, 2009 Dec. 5, 2009 JointJoint Joint Joint length General Root length General length GeneralLength General Root (cm) rating rating (cm) rating (cm) rating (cm)rating rating ADS-20 20-23  2-2.5 1 25-28 1.5-2.5 18-20 1-2 18-20 1-21-2 Hill's Special 15-20 1-2 1 18-28  1-2.5 15-20 1-2 Tall Utah 52-70‘R’ 13-18 1 1 18-23 0-2 13-15 1  0-20 0-2 1 Tall Utah 52-75 13-18 0.5-1 1 13-23 1-2 10-15 1  0-18 0-2 1-2 Conquistador 15-23  1-1.5 1 15-23 1-2.5 15-20 1-2 18-23 1-2 1-2 Sonora 18-20 1 1 18-20 1-2 15-18 1-213-23 1-2 1-2 Challenger 23-35 1-5 18-23 1-3 Command 20-28  3-3.5 125-38 2.5-4  VTR 1330 23-30 1-3 1-2 ADS-16 25-30 2-4 1-2 28-33 4 ADS-120-23 3 1-2 25-28 2.5-3.5  8-20 1-2 23-25 2-4 1-3 Joint length ispresented in centimeters Ratings are from 0 to 5 (0 = Dead and 5 =Resistant) and may be presented as a range expressed within the varietyJun. 6, 2010 Dec. 5, 2010 Joint Joint length General Root length GeneralRoot (cm) rating rating (cm) rating rating ADS-20 20-28 3.5 2-3 23 2 2Hill's Special Tall Utah 52-70 ‘R’ 13-20 0-1 1 18-25 1 0-1 Tall Utah52-75 15-23 1 1 Conquistador 20-23 1-2 1-2 20-23 2 0-1 Sonora 10-20 1 118-23 1-2 1-2 Challenger 20-28 2.5-3  2-3 Command VTR 1330 ADS-16 33-353 2-3 ADS-1 20-28 2-3 2-3 23 2 2 Joint length is presented incentimeters Ratings are from 0 to 5 (0 = Dead and 5 = Resistant) and arepresented as a range expressed within the variety

As shown in Table 7, ADS-20 does not possess significant tolerance tofusarium but is slightly improved over Hill's Special.

Table 8 shows data from an Oxnard, Calif. trial grown in conditionsfairly free of fusarium and evaluated on Jun. 20, 2009. The plantpopulation was 63,360 plants per acre. Color values are from the MunsellColor Chart.

TABLE 8 ADS-20 Hill's Special Conquistador Sonora Challenger ADS-1 TopWidth (cm) Average 36.10 39.00 36.40 40.30 31.80 28.60 Range (32-39)(36-45) (32-40) (36-46) (24-41) (22-34) Plant Height (cm) Average 71.9079.00 71.10 60.80 77.30 79.30 Range (67-76) (74-83) (66-76) (38-70)(73-84) (74-84) Whole Plant weight (kg) Average 1.17 1.23 1.02 0.86 1.051.24 Range (0.85-1.57) (0.87-1.48) (0.55-1.33) (0.52-1.19) (0.70-1.37)(1.05-1.50) Trimmed Plant Weight Average 0.96 1.00 0.80 0.66 0.84 1.00(kg) Range (0.70-1.28) (0.74-1.20) (0.39-1.02) (0.41-0.89) (0.57-1.10)(0.83-1.23) Number of Outer Average 12.10 12.30 12.80 12.30 11.80 12.90Petioles (>40 cm) Range  (9-14) (10-14)  (9-15) (11-15) (10-14) (11-15)Number of Inner Average 6.60 6.90 8.40 7.40 6.90 8.50 Petioles (<40 cm)Range (5-9) (5-9)  (7-10) (6-9) (5-8)  (7-10) Length of Outer PetiolesAverage 35.17 35.70 32.73 32.20 34.67 32.43 to the joint (cm) Range(32-39) (31-35) (30-35) (28-35) (30-38) (29-34) Width of Outer PetiolesAverage 26.40 26.80 24.13 22.50 25.40 29.40 at the midrib (mm) Range(22-30) (24-29) (21-28) (17-27) (21-30) (28-31) Thickness of OuterAverage 9.63 10.03 8.23 7.53 10.20 9.97 Petioles at midrib (mm) Range (9-11)  (9-11)  (7-10) (7-9)  (8-14)  (9-11) Petiole Color 5gy6/65gy5/6  5gy5/6  5gy5/6  5gy5/6  5gy6/6 Leaf Color 5gy3/6 5gy 3/4 5gy 4/45gy 3/4 5gy 3/4 5gy4/4 Petiole Smoothness Smooth Smooth Smooth-slightSmooth-slight Ribby Smooth-Slight rib rib rib Petiole Cup Cup Cup CupCup Cup Cup

As shown in Table 8, ADS-20 was similar to Hill's Special except topwidth and plant height which where smaller and more similar toConquistador.

Table 9 shows data from an Oxnard, Calif. trial grown in conditions withfusarium and evaluated on Dec. 10, 2010. The plant population was 58,080plants per acre. ADS-20 was compared to several varieties includingHill's Special.

TABLE 9 Tall Utah 52- ADS-20 Hill's Special Conquistador Sonora 70 ‘R’Strain ADS-1 Plant Height (cm) Average 52.8 51.1 50.9 53.7 49.3 57.7Range (47-60) (44-61) (47-58) (49-57) (43-54) (51-62) Whole Plant weight(kg) Average 0.5 0.5 0.4 0.4 0.3 0.4 Range (0.29-0.71) (0.25-0.69)(0.26-0.64) (0.29-0.73) (0.22-0.45) (0.22-0.64) Trimmed Plant WeightAverage 0.4 0.4 0.4 0.4 0.3 0.4 (kg) Range (0.26-0.63) (0.22-0.65)(0.23-0.56) (0.25-0.65)  (0.2-0.41)  (0.2-0.56) Number of Outer Average7.8 7.3 7.2 9.2 7.0 7.2 Petioles (>40 cm) Range  (6-10)  (5-10) (6-8) (6-11)  (5-10) (6-8) Number of Inner Average 3.5 3.5 5.2 5.2 4.5 4.4Petioles (<40 cm) Range (3-4) (3-4) (3-7) (3-7) (2-6) (3-7) Length ofOuter Petioles Average 22.5 21.8 20.3 22.4 22.6 20.5 to the joint (cm)Range (19.3-26.3) (17.2-27.2) (16.7-22.7) (19.3-26.3)  (19-24.7)(19.3-21.3) Width of Outer Petioles Average 16.9 16.5 14.5 15.5 14.315.7 at the midrib (mm) Range (13.3-20.3) (13.1-19.1)  (12-17.7)(12.3-19.3)  (12-17.3) (12.7-19.7) Thickness of Outer Average 6.8 6.86.4 6.3 6.8 7.5 Petioles at the midrib Range (5.7-9.3) (5.6-9.4)(3.7-7.3) (4.7-9)   (6-8.7) (5.7-9.3) (mm) Petiole Color (Munsell ColorChart) 5gy 6/6 5gy 6/6 5gy 5/6 5gy 5/6 5gy 6/6 5gy 6/6 Leaf Color(Munsell 5gy 4/4 5gy 4/4 5gy 4/4 5gy 4/4 5gy 4/4 5gy 4/4 Color Chart)Smoothness Smooth - Smooth - Slight rib Smooth Ribby Smooth - slight ribslight rib slight rib Cup Slight cup - Slight cup - Cup Slight cup -Slight cup Cup cup cup cup

In the particular trial shown in Table 9 all of the cultivars werefairly similar for plant height, plant weights, number of petioles andthe measurements for the outer petioles. The only real differencesbetween varieties were slightly lighter weights whole stalk and trimmedfor Tall Utah 52-70 ‘R’ Strain and higher outer petiole count forSonora. Under these fusarium conditions these varieties did not resembletheir normal characteristics and true differences fell away. All appearto be fairly similar in response/appearance.

Table 10 shows data from an Oxnard, Calif. trial grown in conditionswith high levels of fusarium. This particular trial site has beenspecially developed with elevated fusarium levels in order to screen andevaluate celery varieties. This particular trial was evaluated on Dec.9, 2008. The plant population was 58,080 plants per acre. ADS-20 wascompared to several other varieties including Hill's Special.

TABLE 10 Tall Utah 52- ADS-20 Hill's Special Conquistador Sonora 70 ‘R’Strain ADS-1 Plant Height (cm) Average 62.7 61.8 51.8 53.9 52.2 75.2Range (58-68) (53-65) (45-61) (38-63) (45-59) (69-81) Whole Plant weight(kg) Average 0.5 0.5 0.4 0.4 0.5 0.9 Range (0.37-0.73)  (0.3-0.89)(0.11-0.52) (0.04-0.73) (0.16-0.8)  (0.46-1.5)  Trimmed Plant WeightAverage 0.4 0.4 0.3 0.3 0.4 0.7 (kg) Range (0.35-0.66) (0.28-0.74) (0.1-0.48) (0.04-0.64) (0.13-0.74) (0.36-1.24) Number of Outer Average8.1 7.7 7.4 6.6 8.7 9.3 Petioles (>40 cm) Range  (7-10) (6-9) (5-9) (0-11)  (6-12)  (7-12) Number of Inner Average 5.0 5.9 6.3 6.5 7.1 4.4Petioles (<40 cm) Range (3-6) (4-8) (4-9) (5-9)  (6-10) (2-7) Length ofOuter Petioles Average 26.9 25.5 23.0 20.8 21.8 29.4 to the joint (cm)Range  (24-29.3) (21.7-28.3) (20.7-25)  (14.3-27.3) (19.3-24.3) (26-32.3) Width of Outer Petioles Average 19.2 18.0 13.5 14.9 15.4 20.6at the midrib (mm) Range  (17-22.7) (10.7-22.3)  (6.3-20.3)  (7.3-19.3)(10.3-19.7) (15.3-26.3) Thickness of Outer Average 8.2 8.2 6.2 6.3 6.610.2 Petioles at the midrib Range (7.7-9.3)  (6-10) (3-9) (2.7-9)  (5-8.7) (7.3-13)  (mm) Petiole Color (Munsell Color Chart) 5gy 6/6 5gy7/8 5gy 7/8 5gy 6/6 5gy 6/6 5gy 6/6 Leaf Color (Munsell 5gy 4/4 5gy 4/45gy 4/4 5gy 4/4 5gy 4/4 5gy 4/4 Color Chart) Smoothness Smooth SmoothRibby Ribby Ribby Ribby Cup Cup Cup Cup Cup Cup Cup

Under the fusarium conditions experienced in the trial shown in Table10, ADS-1 was capable of producing the largest stalks when consideringheight, weights, outer petiole counts and petiole measurements for widthand thickness. ADS-20 was more stunted than ADS-1, but was second to itfor overall height, petiole length and petiole width. Otherwise it wasvery similar to Hill's Special and performed better than Conquistadorand Sonora.

Table 11 shows a comparison between cultivar ADS-20, Hill's Special andseveral other cultivars grown in Oxnard, Calif. under conditions ofstrong bolting pressure and evaluated on May 4, 2008. An ‘*’ representsthis missing data. Plant population was 58,080 plants per acre.

TABLE 11 Hill's Tall Utah Tall Utah ADS-20 Special 52-70 ‘R’ Strain52-75 Conquistador Top Width (cm) Average 38.9 42.9  * * * Range (36-42)(36-50) Plant Height (cm) Average 72   70.6  * * * Range (70-77) (69-73)Whole Plant weight (kg) Average  1.1 1.0 * * * Range (1.0-1.3) (0.8-1.16) Trimmed Plant Weight (kg) Average  0.9 0.8 * * * Range (0.8-1.07  (0.7-0.98) Number of Outer Average 12   12.6  * * * Petioles(>40 cm) Range (10-14) (10-14) Number of Inner Average  7.7 6.5 * * *Petioles (<40 cm) Range (6-9) (5-8) Length of Outer Petioles Average34.7 35.8  * * * to the joint (cm) Range (33-39) (33-38) Width of OuterPetioles Average 27.4 25.0  * * * at the midrib (mm) Range 26-29 (23-28)Thickness of Outer Average 10.2 9.2 * * * Petioles at midrib (mm) Range(10-11) (7.3-11)  Petiole Color 0  1.9 68.5 58.6 39.9 Leaf Color 0  0.067.0 56.0 36.5 Petiole Smoothness (0-0)  (0-14) (47-92) (45-79) (29-58)Petiole Cup 5gy 6/6 5gy 6/6 * * * Sonora Challenger Mission ADS-1 TopWidth (cm) Average * * * * Range Plant Height (cm) Average * * * * RangeWhole Plant weight (kg) Average * * * * Range Trimmed Plant Weight (kg)Average * * * * Range Number of Outer Average * * * * Petioles (>40 cm)Range Number of Inner Average * * * * Petioles (<40 cm) Range Length ofOuter Petioles Average * * * * to the joint (cm) Range Width of OuterPetioles Average * * * * at the midrib (mm) Range Thickness of OuterAverage * * * * Petioles at midrib (mm ) Range Petiole Color 55.7 48.328.0 39.4 Leaf Color 54.0 46.0 29.0 30.0 Petiole Smoothness (47-69)(36-68) (12-47) (4-47) Petiole Cup * * * *

As shown in Table 11, all varieties except ADS-20 and Hill's Special hadsevere seed stem development and were too distorted for collection ofseveral data points. While ADS-20 and Hill's Special were bothconsiderably more tolerant than all other cultivars tested, ADS-20 wasmore uniform for tolerance to bolting than Hill's Special.

The use of the terms “a,” “an,” and “the,” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. Forexample, if the range 10-15 is disclosed, then 11, 12, 13, and 14 arealso disclosed. All methods described herein can be performed in anysuitable order unless otherwise indicated herein or otherwise clearlycontradicted by context. The use of any and all examples, or exemplarylanguage (e.g., “such as”) provided herein, is intended merely to betterilluminate the invention and does not pose a limitation on the scope ofthe invention unless otherwise claimed. No language in the specificationshould be construed as indicating any non-claimed element as essentialto the practice of the invention.

DEPOSIT INFORMATION

A deposit of the celery cultivar seed of this invention is maintained byA. Duda & Sons, Inc., 1260 Growers Street, Salinas, Calif. 93902, U.S.A.Access to this deposit will be available during the pendency of thisapplication to persons determined by the Commissioner of Patents andTrademarks to be entitled thereto under 37 CFR §1.14 and 35 USC §122.Upon allowance of any claims in this application, all restrictions onthe availability to the public of the variety will be irrevocablyremoved by affording access to a deposit of at least 2,500 seeds of thesame variety with the American Type Culture Collection (ATCC), 10801University Boulevard, Manassas, Va. 20110 or National Collections ofIndustrial, Food and Marine Bacteria (NCIMB), 23 St Machar Drive,Aberdeen, Scotland, AB24 3RY, United Kingdom.

While a number of exemplary aspects and embodiments have been discussedabove, those of skill in the art will recognize certain modifications,permutations, additions, and sub-combinations thereof. It is thereforeintended that the following appended claims and claims hereafterintroduced are interpreted to include all such modifications,permutations, additions, and sub-combinations as are within their truespirit and scope.

1. A seed of celery cultivar ADS-20, wherein a representative sampleseed of said cultivar was deposited under ATCC Accession No. PTA-______.2. A celery plant, or a part thereof, produced by growing the seed ofclaim
 1. 3. A tissue culture produced from protoplasts or cells from theplant of claim 2, wherein said cells or protoplasts are produced from aplant part selected from the group consisting of leaf, callus, pollen,ovule, embryo, cotyledon, hypocotyl, meristematic cell, root, root tip,pistil, anther, flower, seed, shoot, stem, petiole and sucker.
 4. Acelery plant regenerated from the tissue culture of claim 3, wherein theplant has all of the morphological and physiological characteristics ofcultivar ADS-20.
 5. A method for producing a celery seed comprisingcrossing two celery plants and harvesting the resultant celery seed,wherein at least one celery plant is the celery plant of claim
 2. 6. Acelery seed produced by the method of claim
 5. 7. A celery plant, or apart thereof, produced by growing said seed of claim
 6. 8. The method ofclaim 5, wherein at least one of said celery plants is transgenic.
 9. Amethod of producing a herbicide resistant celery plant, wherein saidmethod comprises introducing a gene conferring herbicide resistance intothe plant of claim
 2. 10. A herbicide resistant celery plant produced bythe method of claim 9, wherein the gene confers resistance to aherbicide selected from the group consisting of glyphosate,sulfonylurea, imidazolinone, dicamba, glufosinate, phenoxy proprionicacid, L-phosphinothricin, cyclohexone, cyclohexanedione, triazine, andbenzonitrile.
 11. A method of producing a pest or insect resistantcelery plant, wherein said method comprises introducing a geneconferring pest or insect resistance into the celery plant of claim 2.12. A pest or insect resistant celery plant produced by the method ofclaim
 11. 13. The celery plant of claim 12, wherein the gene encodes aBacillus thuringiensis (Bt) endotoxin.
 14. A method of producing adisease resistant celery plant, wherein said method comprisesintroducing a gene into the celery plant of claim
 2. 15. A diseaseresistant celery plant produced by the method of claim
 14. 16. A methodfor producing a male sterile celery plant, wherein said method comprisestransforming the celery plant of claim 2, with a nucleic acid moleculethat confers male sterility.
 17. A male sterile celery plant produced bythe method of claim
 16. 18. A method of introducing a desired trait intocelery cultivar ADS-20 wherein the method comprises: (a) crossing aADS-20 plant, wherein a representative sample of seed was depositedunder ATCC Accession No. PTA-______, with a plant of another celerycultivar that comprises a desired trait to produce progeny plantswherein the desired trait is selected from the group consisting ofimproved nutritional quality, industrial usage, male sterility,herbicide resistance, insect resistance, modified seed yield, modifiedlodging resistance, modified iron-deficiency chlorosis and resistance tobacterial disease, fungal disease or viral disease; (b) selecting one ormore progeny plants that have the desired trait to produce selectedprogeny plants; (c) crossing the selected progeny plants with the ADS-20plants to produce backcross progeny plants; (d) selecting for backcrossprogeny plants that have the desired trait and all of the physiologicaland morphological characteristics of celery cultivar ADS-20 listed inTable 1; and (e) repeating steps (c) and (d) two or more times insuccession to produce selected third or higher backcross progeny plantsthat comprise the desired trait and all of the physiological andmorphological characteristics of celery cultivar ADS-20 listed inTable
 1. 19. A celery plant produced by the method of claim 18, whereinthe plant has the desired trait.
 20. The celery plant of claim 19,wherein the desired trait is herbicide resistance and the resistance isconferred to a herbicide selected from the group consisting ofimidazolinone, dicamba, cyclohexanedione, sulfonylurea, glyphosate,glufosinate, phenoxy proprionic acid, L-phosphinothricin, triazine andbenzonitrile.
 21. The celery plant of claim 19, wherein the desiredtrait is insect resistance and the insect resistance is conferred by agene encoding a Bacillus thuringiensis endotoxin.
 22. The celery plantof claim 19, wherein the desired trait is male sterility and the traitis conferred by a cytoplasmic nucleic acid molecule.
 23. A method ofproducing a celery plant with modified fatty acid metabolism or modifiedcarbohydrate metabolism comprising transforming the celery plant ofclaim 2 with a transgene encoding a protein selected from the groupconsisting of fructosyltransferase, levansucrase, α-amylase, invertaseand starch branching enzyme or encoding an antisense of stearyl-ACPdesaturase.
 24. A celery plant having modified fatty acid metabolism ormodified carbohydrate metabolism produced by the method of claim 23.